Terminal device and base station device

ABSTRACT

A terminal device includes a reception unit which performs first measurement when a predetermined cell is in a first state and second measurement when the predetermined cell is in a second state, and a higher layer processing unit which reports the first measurement or the second measurement to a base station device. Based on information indicating the first state/the second state of the predetermined cell, the first measurement and the second measurement are switched.

TECHNICAL FIELD

The present invention relates to a terminal device and a base stationdevice.

This application claims priority based on Japanese Patent ApplicationNo. 2014-058193 filed in Japan on Mar. 20, 2014, the content of which isincorporated herein.

BACKGROUND ART

A radio access scheme and a radio network of cellular mobilecommunication (hereinafter, referred to as “Long Term Evolution (LTE)”or “Evolved Universal Terrestrial Radio Access: EUTRA”) have beenstudied in the 3rd Generation Partnership Project (3GPP). In the LTE, abase station device (base station) is also referred to as an eNodeB(evolved NodeB) and a terminal device (mobile station, mobile stationdevice, terminal) is also referred to as UE (User Equipment). The LTE isa cellular communication system in which a plurality of areas covered bybase station devices are arranged in a cell-like shape. A single basestation device may manage a plurality of cells.

The LTE is ready for Frequency Division Duplex (FDD) and Time DivisionDuplex (TDD). The LTE employing a FDD scheme is also referred to asFD-LTE or LTE FDD. The TDD is a technique that allows full-duplexcommunication in at least two frequency bands by performingfrequency-division multiplexing of an uplink signal and a downlinksignal. The LTE employing a TDD scheme is also referred to as TD-LTE orLTE TDD. The TDD is a technique that allows full-duplex communication ina single frequency band by performing time-division multiplexing of anuplink signal and a downlink signal. Details of the FD-LTE and theTD-LTE are disclosed in NPL 1.

A base station device is able to transmit, to a terminal device, areference signal (also referred to as RS) which is a known signalbetween the base station device and the terminal device. A plurality ofreference signals may be transmitted for various purposes such asdemodulation of a signal and a channel and reporting of a channel state.For example, a cell-specific reference signal is transmitted in alldownlink subframes as a reference signal specific to a cell. Inaddition, for example, a terminal-specific reference signal istransmitted as a reference signal specific to a terminal device in aresource in which a data signal to the terminal device is mapped.Details of the reference signals are disclosed in NPL 1.

In the 3GPP, introduction of a small cell has been studied. A small cellis a collective term indicating a cell in which transmit power of a basestation device forming the cell is small and which has smaller coveragethan that of a conventional cell (macro cell). For example, when smallcells are applied with a high frequency band, it is possible to arrangethe small cells at high density and an effect of improving spectralefficiency per area is achieved. In the study of introduction of a smallcell, discussion on a technique of switching the base station device toa stop state for various purposes such as reduction in power consumptionand reduction in inter-cell interference has been carried out. Detailsthereof are disclosed in NPL 2.

CITATION LIST Non Patent Literature

-   NPL 1: 3rd Generation Partnership Project; Technical Specification    Group Radio Access Network; Evolved Universal Terrestrial Radio    Access (E-UTRA); Physical Channels and Modulation (Release 11), 3GPP    TS 36.211 V11.5.0 (2014 January).-   NPL 2: 3rd Generation Partnership Project; Technical Specification    Group Radio Access Network; Small cell enhancements for E-UTRA and    E-UTRAN-Physical layer aspects (Release 12), 3GPP TR 36.872 V12.1.0    (2013 December).

SUMMARY OF INVENTION Technical Problem

However, when the base station device is switched to the stop state,transmission of a synchronization signal and a reference signal is alsostopped. Therefore, it is difficult for a terminal device to find thebase station device in the stop state. In such a situation, it takes along time for preparation for connecting the terminal device to the basestation device in the stop state, which causes great deterioration intransmission efficiency.

The invention provides a base station device, a terminal device, acommunication system, a communication method, and an integrated circuitwhich are able to improve transmission efficiency in a communicationsystem in which the base station device communicates with the terminaldevice.

Solution to Problem

(1) The invention takes following means. That is, a terminal deviceaccording to an embodiment of the invention includes: a measurement unitwhich performs first measurement for performing measurement by using afirst reference signal and second measurement for performing measurementby using a second reference signal; a reception unit which receivesinformation on criteria for triggering of a measurement reporting event;and a transmission unit which transfers a measurement message includinga measurement result, in which the information on criteria fortriggering of the measurement reporting event includes information ontriggering criteria of an event of a first measurement reporting andinformation on triggering criteria of an event of a second measurementreporting, and the measurement message includes a result of the firstmeasurement in a case where the first measurement reporting is triggeredand includes a result of the second measurement in a case where thesecond measurement reporting is triggered.

(2) In the terminal device according to another embodiment of theinvention, the information on triggering criteria of the event of thefirst measurement reporting includes first information for specifying atriggering quantity used for evaluating criteria for triggering of anevent of a measurement reporting related to the first reference signal.

(3) In the terminal device according to another embodiment of theinvention, the first information is information indicating RSRP or RSRQ.

(4) In the terminal device according to another embodiment of theinvention, the first reference signal is a CRS.

(5) In the terminal device according to another embodiment of theinvention, the information on triggering criteria of the event of thesecond measurement reporting includes second information for specifyinga triggering quantity used for evaluating criteria for triggering of anevent of a measurement reporting related to the second reference signal.

(6) In the base station device according to another embodiment of theinvention, the second information is information indicating RSRP.

(7) In the base station device according to another embodiment of theinvention, the second reference signal is a CSI-RS.

(8) A base station device according to another embodiment of theinvention includes: a transmission unit which transmits information oncriteria for triggering of a measurement reporting event; and areception unit which receives a measurement message including ameasurement result, in which the information on criteria for triggeringof the measurement reporting event includes information on triggeringcriteria of an event of a first measurement reporting and information ontriggering criteria of an event of a second measurement reporting, andthe measurement message includes a result of first measurement forperforming measurement by using a first reference signal in a case wherethe first measurement reporting is triggered and includes a result ofsecond measurement for performing measurement by using a secondreference signal in a case where the second measurement reporting istriggered.

(9) In the base station device according to another embodiment of theinvention, the information on triggering criteria of the event of thefirst measurement reporting includes first information for specifying atriggering quantity used for evaluating criteria for triggering of anevent of a measurement reporting related to the first reference signal.

(10) In the base station device according to another embodiment of theinvention, the first information is information indicating RSRP or RSRQ.

(11) In the base station device according to another embodiment of theinvention, the first reference signal is a CRS.

(12) In the base station device according to another embodiment of theinvention, the information on triggering criteria of the event of thesecond measurement reporting includes second information for specifyinga triggering quantity used for evaluating criteria for triggering of anevent of a measurement reporting related to the second reference signal.

(13) In the base station device according to another embodiment of theinvention, the second information is information indicating RSRP.

(14) In the base station device according to another embodiment of theinvention, the second reference signal is a CSI-RS.

(15) A communication method performed by a terminal device according toanother embodiment of the invention includes: a step of performing firstmeasurement for performing measurement by using a first reference signaland second measurement for performing measurement by using a secondreference signal; a step of receiving information on criteria fortriggering of a measurement reporting event; and a step of transferringa measurement message including a measurement result, in which theinformation on criteria for triggering of the measurement reportingevent includes information on triggering criteria of an event of a firstmeasurement reporting and information on triggering criteria of an eventof a second measurement reporting, and the measurement message includesa result of the first measurement in a case where the first measurementreporting is triggered and includes a result of the second measurementin a case where the second measurement reporting is triggered.

(16) A communication method performed by a base station device accordingto another embodiment of the invention includes: a step of transmittinginformation on criteria for triggering of a measurement reporting event;and a step of receiving a measurement message including a measurementresult, in which the information on criteria for triggering of themeasurement reporting event includes information on triggering criteriaof an event of a first measurement reporting and information ontriggering criteria of an event of a second measurement reporting, andthe measurement message includes a result of first measurement forperforming measurement by using a first reference signal in a case wherethe first measurement reporting is triggered and includes a result ofsecond measurement for performing measurement by using a secondreference signal in a case where the second measurement reporting istriggered.

(17) An integrated circuit mounted in a terminal device according toanother embodiment of the invention includes: a function of performingfirst measurement for performing measurement by using a first referencesignal and second measurement for performing measurement by using asecond reference signal; a function of receiving information on criteriafor triggering of a measurement reporting event; and a function oftransferring a measurement message including a measurement result, inwhich the information on criteria for triggering of the measurementreporting event includes information on triggering criteria of an eventof a first measurement reporting and information on triggering criteriaof an event of a second measurement reporting, and the measurementmessage includes a result of the first measurement in a case where thefirst measurement reporting is triggered and includes a result of thesecond measurement in a case where the second measurement reporting istriggered.

(18) An integrated circuit mounted in a base station device according toanother embodiment of the invention includes: a function of transmittinginformation on criteria for triggering of a measurement reporting event;and a function of receiving a measurement message including ameasurement result, in which the information on criteria for triggeringof the measurement reporting event includes information on triggeringcriteria of an event of a first measurement reporting and information ontriggering criteria of an event of a second measurement reporting, andthe measurement message includes a result of first measurement forperforming measurement by using a first reference signal in a case wherethe first measurement reporting is triggered and includes a result ofsecond measurement for performing measurement by using a secondreference signal in a case where the second measurement reporting istriggered.

Advantageous Effects of Invention

According to the invention, it is possible to improve transmissionefficiency in a radio communication system in which a base stationdevice communicates with a terminal device.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a conceptual view of a radio communication system of thepresent embodiment.

FIG. 2 illustrates a schematic configuration of a radio frame of thepresent embodiment.

FIG. 3 illustrates a configuration of a slot of the present embodiment.

FIG. 4 illustrates one example of arrangement of a physical channel anda physical signal in a downlink subframe of the present embodiment.

FIG. 5 illustrates one example of arrangement of a physical channel anda physical signal in an uplink subframe of the present embodiment.

FIG. 6 illustrates one example of arrangement of a physical channel anda physical signal in a special subframe of the present embodiment.

FIG. 7 is a schematic block diagram illustrating a configuration of aterminal device 1 of the present embodiment.

FIG. 8 is a schematic block diagram illustrating a configuration of abase station device 3 of the present embodiment.

FIG. 9 illustrates one example of arrangement of a DRS.

FIG. 10 illustrates one example of arrangement of the DRS.

FIG. 11 illustrates one example of arrangement of the DRS.

FIG. 12 illustrates one example of designation of a resource element toa configuration of the DRS.

FIG. 13 illustrates a model of measurement.

DESCRIPTION OF EMBODIMENTS

Description will hereinafter be given in detail for embodiments of theinvention.

In the present embodiment, a plurality of cells are configured to aterminal device. A technique in which the terminal device performscommunication through a plurality of cells is referred to as cellaggregation, carrier aggregation, or dual connectivity. The inventionmay be applied to each of the plurality of cells configured to theterminal device. The invention may be applied to a part of the pluralityof configured cells. Cells configured to the terminal device are alsoreferred to as serving cells.

In the carrier aggregation, a plurality of serving cells which areconfigured include one primary cell (PCell) and one or more secondarycells (SCell). The primary cell is a serving cell in which initialconnection establishment procedure is performed, a serving cell in whichconnection re-establishment procedure is started, or a cell which isinstructed as a primary cell in handover procedure. The secondary cellsmay be configured at a time when or after RRC connection is established.

The dual connectivity is an operation in which radio resources providedby at least two different network points (a master base station deviceand a secondary base station device) which are connected by non-idealbackhaul are consumed by a predetermined terminal device in an RRCconnected (RRC_CONNECTED) state.

In the dual connectivity, a base station device that is connected to atleast S1-MME (Mobility Management Entity) and functions as a mobilityanchor of a core network is referred to as a master base station device(Master eNB). A base station device that provides a terminal device withan additional radio resource and is not the master base station deviceis referred to as a secondary base station device. A group of servingcells related to the master base station device is referred to as aMaster Cell Group and a group of serving cells related to the secondarybase station device is referred to as a Secondary Cell Group.

A FDD (Frequency Division Duplex) or TDD (Time Division Duplex) schemeis applied to a radio communication system of the present embodiment. Inthe case of the cell aggregation, the TDD scheme may be applied to allof a plurality of cells. Moreover, in the case of the cell aggregation,cells to which the TDD scheme is applied and cells to which the FDDscheme is applied may be aggregated. When the cells to which the TDD isapplied and the cells to which the FDD is applied are aggregated, theinvention is able to be applied to the cells to which the TDD isapplied.

When the plurality of cells to which the TDD is applied are aggregated,a half-duplex TDD scheme or a full-duplex TDD scheme is able to beapplied.

A terminal device transmits, to a base station device, informationindicating combinations of bands supporting the carrier aggregation bythe terminal device. The terminal device transmits, to the base stationdevice, information for specifying whether or not each of thecombinations of bands supports simultaneous transmission and receptionin the plurality of serving cells in a plurality of different bands.

In the present embodiment, “X/Y” includes meaning of “X or Y”. In thepresent embodiment, “X/Y” includes meaning of “X and Y”. In the presentembodiment, “X/Y” includes meaning of “X and/or Y”.

FIG. 1 is a conceptual view of the radio communication system of thepresent embodiment. In FIG. 1, the radio communication system includesterminal devices 1A to 1C and a base station device 3. The terminaldevices 1A to 1C are referred to as a terminal device 1 below.

A physical channel and a physical signal of the present embodiment willbe described.

In FIG. 1, an uplink physical channel is used in uplink radiocommunication from the terminal device 1 to the base station device 3.The uplink physical channel is able to be used to transmit informationoutput from a higher layer. The uplink physical channel includes PUCCH(Physical Uplink Control Channel), PUSCH (Physical Uplink SharedChannel), PRACH (Physical Random Access Channel), and the like.

The PUCCH is a physical channel used to transmit uplink controlinformation (UCI). The uplink control information includes downlinkchannel state information (CSI), a scheduling request (SR) indicating arequest of a PUSCH resource, and ACK (acknowledgement)/NACK(negative-acknowledgement) to downlink data (Transport block,Downlink-Shared Channel: DL-SCH). The ACK/NACK is also referred to asHARQ-ACK, HARQ feedback, or response information.

The PUSCH is a physical channel used to transmit uplink data(Uplink-Shared Channel: UL-SCH). Further, the PUSCH may be used totransmit HARQ-ACK and/or channel state information together with theuplink data. The PUSCH may be used to transmit only channel stateinformation or only HARQ-ACK and channel state information.

The PRACH is a physical channel used to transmit a random accesspreamble. A main purpose of the PRACH is to allow the terminal device 1to acquire synchronization with the base station device 3 in a timedomain. In addition, the PRACH is also used for initial connectionestablishment procedure, handover procedure, connection re-establishmentprocedure, synchronization for uplink transmission (timing adjustment),and a request for PUSCH resources.

In FIG. 1, an uplink physical signal is used in the uplink radiocommunication. The uplink physical signal includes an uplink referencesignal (UL RS) and the like. For the uplink reference signal, a DMRS(Demodulation Reference Signal), an SRS (Sounding Reference Signal), andthe like are used. The DMRS is associated with transmission of the PUSCHor the PUCCH. The DMRS is time-multiplexed with the PUSCH or the PUCCH.The base station device 3 uses the DMRS to perform channel correction ofthe PUSCH or the PUCCH. Hereinafter, simultaneous transmission of thePUSCH and the DMRS is simply referred to as transmission of the PUSCH.Hereinafter, simultaneous transmission of the PUCCH and the DMRS issimply referred to as transmission of the PUCCH. Note that, the DMRS ofuplink is also referred to as UL-DMRS. The SRS is not associated withtransmission of the PUSCH or the PUCCH. The base station device 3 usesthe SRS to measure a channel state of uplink.

In FIG. 1, a downlink physical channel is used in downlink radiocommunication from the base station device 3 to the terminal device 1.The downlink physical channel is able to be used to transmit informationoutput from a higher layer. The downlink physical channel includes PBCH(Physical Broadcast Channel), PCFICH (Physical Control Format IndicatorChannel), PHICH (Physical Hybrid automatic repeat request IndicatorChannel), PDCCH (Physical Downlink Control Channel), EPDCCH (EnhancedPhysical Downlink Control Channel), PDSCH (Physical Downlink SharedChannel), PMCH (Physical Multicast Channel), and the like.

The PBCH is used to broadcast a master information block (MIB, BroadcastChannel: BCH) which is shared by the terminal device 1. The MIB is ableto be updated at an interval of 40 ms. The PBCH is repeatedlytransmitted with a period of 10 ms. Specifically, initial transmissionof the MIB is performed in a subframe 0 of a radio frame satisfying SFNmod 4=0 and retransmission (repetition) of the MIB is performed insubframes 0 of all other radio frames. The SFN (system frame number) isa number of a radio frame. The MIB is system information. For example,the MIB includes information indicating the SFN.

The PCFICH is used to transmit information for instructing a domain(OFDM symbol) used for transmission of the PDCCH.

The PHICH is used to transmit a HARQ indicator (HARQ feedback, responseinformation) indicating ACK (ACKnowledgement) or NACK (NegativeACKnowledgement) to uplink data (Uplink Shared Channel: UL-SCH) receivedby the base station device 3. For example, when the terminal device 1receives a HARQ indicator indicating ACK, corresponding uplink data isnot retransmitted. For example, when the terminal device 1 receives aHARQ indicator indicating NACK, corresponding uplink data isretransmitted. A single PHICH transmits a HARQ indicator for singleuplink data. The base station device 3 transmits HARQ indicators for aplurality of pieces of uplink data contained in the same PUSCH by usinga plurality of PHICHs.

The PDCCH and the EPDCCH are used to transmit downlink controlinformation (DCI). The downlink control information is also referred toas a DCI format. The downlink control information includes a downlinkgrant and an uplink grant. The downlink grant is also referred to asdownlink assignment or downlink allocation.

The downlink grant is used for scheduling of a single PDSCH within asingle cell. The downlink grant is used for scheduling of the PDSCHwithin a subframe that is the same as the subframe in which the downlinkgrant is transmitted. The uplink grant is used for scheduling of asingle PUSCH within a single cell. The uplink grant is used forscheduling of a single PUSCH within the fourth or later subframe afterthe subframe in which the uplink grant is transmitted.

CRC (Cyclic Redundancy Check) parity bit is added to the DCI format. TheCRC parity bit is scrambled by C-RNTI (Cell-Radio Network TemporaryIdentifier) or SPS C-RNTI (Semi Persistent Scheduling Cell-Radio NetworkTemporary Identifier). The C-RNTI and the SPS C-RNTI are identifiers foridentifying a terminal device in a cell. The C-RNTI is used to controlthe PDSCH or the PUSCH in a single subframe. The SPS C-RNTI is used toallocate a resource of the PDSCH or the PUSCH periodically.

The PDSCH is used to transmit downlink data (Downlink Shared Channel:DL-SCH).

The PMCH is used to transmit multicast data (Multicast Channel: MCH).

In FIG. 1, following downlink physical signals are used in downlinkradio communication. The downlink physical signals include asynchronization signal (SS), a downlink reference signal (DL RS), andthe like.

The synchronization signal is used for the terminal device 1 to besynchronized in a frequency domain and a time domain of downlink. Thesynchronization signal is arranged in a predetermined subframe within aradio frame. For example, in the TDD scheme, the synchronization signalis arranged in subframes 0, 1, 5, and 6 within the radio frame. In theFDD scheme, the synchronization signal is arranged in subframes 0 and 5within the radio frame.

The downlink reference signal is used for the terminal device 1 toperform channel correction of the downlink physical channel. Thedownlink reference signal is used for the terminal device 1 to calculatedownlink channel state information. The downlink reference signal isused for the terminal device 1 to measure a physical position of theterminal device 1.

The downlink reference signal includes CRS (Cell-specific ReferenceSignal), URS (UE-specific Reference Signal) associated with the PDSCH,DMRS (Demodulation Reference Signal) associated with the EPDCCH, NZPCSI-RS (Non-Zero Power Channel State Information-Reference Signal), ZPCSI-RS (Zero Power Channel State Information-Reference Signal), CSI-IM(Channel State Information-Interference Measurement), MBSFN RS(Multimedia Broadcast and Multicast Service over Single FrequencyNetwork Reference signal), PRS (Positioning Reference Signal), NCT CRS(New Carrier Type Cell-specific Reference Signal), DRS (DiscoveryReference Signal, Discovery Signal), and the like.

The CRS is transmitted in an entire band of a subframe. The CRS is usedto perform demodulation of the PBCH/PDCCH/PHICH/PCFICH/PDSCH. The CRSmay be used for the terminal device 1 to calculate downlink channelstate information. The PBCH/PDCCH/PHICH/PCFICH is transmitted by anantenna port used for transmission of the CRS.

The URS associated with the PDSCH is transmitted in a subframe or bandused for transmission of the PDSCH associated with the URS. The URS isused to perform demodulation of the PDSCH associated with the URS.

The PDSCH is transmitted by an antenna port used for transmission of theCRS or the URS. A DCI format 1A is used for scheduling of the PDSCHtransmitted by an antenna port used for transmission of the CRS. A DCIformat 2D is used for scheduling of the PDSCH transmitted by an antennaport used for transmission of the URS.

The DMRS associated with the EPDCCH is transmitted in a subframe or bandused for transmission of the EPDCCH associated with the DMRS. The DMRSis used to perform demodulation of the EPDCCH associated with the DMRS.The EPDCCH is transmitted by an antenna port used for transmission ofthe DMRS.

The NZP CSI-RS is transmitted in a configured subframe. A resource inwhich the NZP CSI-RS is transmitted is configured by the base stationdevice. The NZP CSI-RS is used for the terminal device 1 to calculatedownlink channel state information. The terminal device 1 performssignal measurement (channel measurement) by using the NZP CSI-RS.

The resource of the ZP CSI-RS is configured by the base station device3. The base station device 3 transmits the ZP CSI-RS with zero power.That is, the base station device 3 does not transmit the ZP CSI-RS. Thebase station device 3 does not transmit the PDSCH or the EPDCCH in theconfigured resource of the ZP CSI-RS.

The resource of the CSI-IM is configured by the base station device 3.The resource of the CSI-IM is configured to overlap with a part of theresource of the ZP CSI-RS. That is, the resource of the CSI-IM hascharacteristics equivalent to those of the ZP CSI-RS, and the basestation device 3 performs transmission with zero power in the resourceconfigured as the CSI-IM. That is, the base station device 3 does nottransmit the CSI-IM. The base station device 3 does not transmit thePDSCH or the EPDCCH in the configured resource of the CSI-IM. In theresource corresponding to the NZP CSI-RS in a certain cell, the terminaldevice 1 is able to measure interference in the resource configured asthe CSI-IM.

The MBSFN RS is transmitted in an entire band of a subframe used fortransmission of the PMCH. The MBSFN RS is used to perform demodulationof the PMCH. The PMCH is transmitted by an antenna port used fortransmission of the MBSFN RS.

The PRS is used for the terminal device to measure a physical positionof the terminal device.

The NCT CRS (TRS) is able to be mapped to a predetermined subframe. Forexample, the NCT CRS is mapped to subframes 0 and 5. The NCT CRS mayhave a configuration partially similar to that of the CRS. For example,in each resource block, a position of a resource element to which theNCT CRS is mapped may be the same as a position of a resource element towhich the CRS of an antenna port 0 is mapped. A sequence (value) usedfor the NCT CRS is able to be determined based on information configuredthrough the PBCH, the PDCCH, the EPDCCH, or the PDSCH (RRC signaling). Asequence (value) used for the NCT CRS is able to be determined based ona parameter such as a cell ID (for example, a physical layer cellidentity) or a slot number. A sequence (value) used for the NCT CRS isable to be determined by a method (scheme) different from the sequence(value) used for the CRS of the antenna port 0.

A downlink physical channel and a downlink physical signal arecollectively referred to as a downlink signal. An uplink physicalchannel and an uplink physical signal are collectively referred to as anuplink signal. A downlink physical channel and an uplink physicalchannel are collectively referred to as a physical channel. A downlinkphysical signal and an uplink physical signal are collectively referredto as a physical signal.

The BCH, the MCH, the UL-SCH, and the DL-SCH are transport channels. Achannel used in a medium access control (MAC) layer is referred to as atransport channel. A unit of the transport channel used in the MAC layeris also referred to as a transport block (TB) or a MAC PDU (ProtocolData Unit). Control of HARQ (Hybrid Automatic Repeat reQuest) isperformed for each transport block in the MAC layer. The transport blockis a unit of data delivered to the physical layer from the MAC layer. Inthe physical layer, the transport block is mapped to a code word andcoding processing is performed for each code word.

As a method of signaling (notification, broadcasting) of controlinformation from the base station device 3 to the terminal device 1,PDCCH signaling which is signaling through the PDCCH, RRC signalingwhich is signaling through an RRC layer, MAC signaling which issignaling through the MAC layer, or the like is used. Moreover, as theRRC signaling, dedicated RRC signaling for notifying control informationspecific to the terminal device 1 and common RRC signaling for notifyingcontrol information specific to the base station device 3 are used. Notethat, in the following description, when simply described as RRCsignaling, the RRC signaling means the dedicated RRC signaling and/orthe common RRC signaling.

A configuration of a radio frame of the present embodiment will bedescribed below.

FIG. 2 illustrates a schematic configuration of a radio frame of thepresent embodiment. Each of radio frames has a 10 ms length. In FIG. 2,a horizontal axis denotes a time axis. Each of the radio frames isconstituted by two half frames. Each of the half frames has a 5 mslength. Each of the half frames is constituted by five subframes. Eachof the subframes has a 1 ms length and is defined by two continuousslots. Each of the slots has a 0.5 ms length. The i-th subframe in aradio frame is constituted by the (2×i)-th slot and the (2×i+1)-th slot.That is, ten subframes are able to be used in each 10 ms period.

The subframe includes a downlink subframe (first subframe), an uplinksubframe (second subframe), a special subframe (third subframe), and thelike.

The downlink subframe is a subframe reserved for downlink transmission.The uplink subframe is a subframe reserved for uplink transmission. Thespecial subframe is constituted by three fields. The three fields are aDwPTS (Downlink Pilot Time Slot), a GP (Guard Period), and an UpPTS(Uplink Pilot Time Slot). A total length of the DwPTS, the GP, and theUpPTS is 1 ms. The DwPTS is a field reserved for downlink transmission.The UpPTS is a field reserved for uplink transmission. The GP is a fieldin which downlink transmission or uplink transmission is not performed.Note that, the special subframe may be constituted by only the DwPTS andthe GP or may be constituted by only the GP and the UpPTS.

A single radio frame is constituted by at least a downlink subframe, anuplink subframe, and a special subframe.

The radio communication system of the present embodiment supportsdownlink-to-uplink switch-point periodicities of 5 ms and 10 ms. Whenthe downlink-to-uplink switch-point periodicity is 5 ms, each of halfframes in the radio frame includes a special subframe. When thedownlink-to-uplink switch-point periodicity is 10 ms, only the firsthalf frame in the radio frame includes a special subframe.

A configuration of a slot of the present embodiment will be describedbelow.

FIG. 3 illustrates a configuration of a slot of the present embodiment.In the present embodiment, normal CP (Cyclic Prefix) is applied to anOFDM symbol. Note that, extended CP (Cyclic Prefix) may be applied tothe OFDM symbol. A physical signal or a physical channel transmitted ineach of the slots is represented by a resource grid. The resource gridin downlink is defined by a plurality of subcarriers in a frequencydirection and a plurality of OFDM symbols in a time direction. Theresource grid in uplink is defined by a plurality of subcarriers in thefrequency direction and a plurality of SC-FDMA symbols in the timedirection. The number of subcarriers or resource blocks depends on abandwidth of a cell. The number of OFDM symbols or SC-FDMA symbolsforming one slot is seven in the case of the normal CP and six in thecase of the extended CP. Each element in the resource grid is referredto as a resource element. The resource element is identified with use ofa subcarrier number and an OFDM symbol or SC-FDMA symbol number.

The resource block is used for mapping to a resource element of acertain physical channel (such as the PDSCH or the PUSCH). In theresource block, a virtual resource block and a physical resource blockare defined. A certain physical channel is firstly mapped to a virtualresource block. Then, the virtual resource block is mapped to a physicalresource block. One physical resource block is defined by sevencontinuous OFDM symbols or SC-FDMA symbols in a time domain and twelvecontiguous subcarriers in a frequency domain. Consequently, one physicalresource block is constituted by (7×12) resource elements. One physicalresource block corresponds to one slot in the time domain andcorresponds to 180 kHz in the frequency domain. Physical resource blocksare numbered starting from 0 in the frequency domain. In addition, tworesource blocks in one subframe, to which the same physical resourceblock number corresponds, are defined as a physical resource block pair(PRB pair, RB pair).

A physical channel and a physical signal transmitted in each of thesubframes will be described below.

FIG. 4 illustrates one example of arrangement of a physical channel anda physical signal in a downlink subframe of the present embodiment. Thebase station device 3 is able to transmit a downlink physical channel(PBCH, PCFICH, PHICH, PDCCH, EPDCCH, PDSCH) and/or a downlink physicalsignal (synchronization signal, downlink reference signal) in thedownlink subframe. Note that, the PBCH is transmitted only in a subframe0 within a radio frame. Note that, the downlink reference signal isarranged in a resource element distributed in the frequency domain andthe time domain. For simplification of the description, the downlinkreference signal is not illustrated in FIG. 4.

In a PDCCH domain, a plurality of PDCCHs may be subjected to frequency,time, and/or spatial multiplexing. In an EPDCCH domain, a plurality ofEPDCCHs may be subjected to frequency, time, and/or spatialmultiplexing. In a PDSCH domain, a plurality of PDSCHs may be subjectedto frequency, time, and/or spatial multiplexing. The PDCCH, the PDSCH,and/or the EPDCCH may be subjected to frequency, time, and/or spatialmultiplexing.

FIG. 5 illustrates one example of arrangement of a physical channel anda physical signal in an uplink subframe of the present embodiment. Theterminal device 1 may transmit an uplink physical channel (PUCCH, PUSCH,PRACH) and an uplink physical signal (UL-DMRS, SRS) in the uplinksubframe. In a PUCCH domain, a plurality of PUCCHs are subjected tofrequency, time, spatial, and/or code multiplexing. In a PUSCH domain, aplurality of PUSCHs may be subjected to frequency, time, spatial, and/orcode multiplexing. The PUCCH and the PUSCH may be subjected tofrequency, time, spatial, and/or code multiplexing. The PRACH may bearranged in a single subframe or over two subframes. A plurality ofPRACHs may be subjected to code multiplexing.

The SRS is transmitted by using the last SC-FDMA symbol in the uplinksubframe. That is, the SRS is arranged in the last SC-FDMA symbol in theuplink subframe. The terminal device 1 is able to limit simultaneoustransmission of the SRS with the PUCCH/PUSCH/PRACH in a single SC-FDMAsymbol of a single cell. In a single uplink subframe of a single cell,the terminal device 1 is able to transmit the PUSCH and/or the PUCCH byusing SC-FDMA symbols other than the last SC-FDMA symbol within theuplink subframe and transmit the SRS by using the last SC-FDMA symbolwithin the uplink subframe. That is, the terminal device 1 is able totransmit the SRS, the PUSCH, and the PUCCH in a single uplink subframeof a single cell. Note that, the DMRS is able to be time-multiplexedwith the PUCCH or the PUSCH. For simplification of the description, theDMRS is not illustrated in FIG. 5.

FIG. 6 illustrates one example of arrangement of a physical channel anda physical signal in a special subframe of the present embodiment. InFIG. 6, the DwPTS is constituted by first to tenth SC-FDMA symbols inthe special subframe, the GP is constituted by eleventh and twelfthSC-FDMA symbols in the special subframe, and the UpPTS is constituted bythirteenth and fourteenth SC-FDMA symbols in the special subframe.

The base station device 3 may transmit the PCFICH, the PHICH, the PDCCH,the EPDCCH, the PDSCH, the synchronization signal, and the downlinkreference signal in the DwPTS of the special subframe. The base stationdevice 3 is able to limit transmission of the PBCH in the DwPTS of thespecial subframe. The terminal device 1 may transmit the PRACH and theSRS in the UpPTS of the special subframe. That is, the terminal device 1is able to limit transmission of the PUCCH, the PUSCH, and the DMRS inthe UpPTS of the special subframe.

FIG. 7 is a schematic block diagram illustrating a configuration of theterminal device 1 of the present embodiment. As illustrated therein, theterminal device 1 includes a higher layer processing unit 101, a controlunit 103, a reception unit 105, a transmission unit 107, and atransmit/receive antenna 109. The higher layer processing unit 101includes a radio resource control unit 1011, a subframe configurationunit 1013, a scheduling information interpretation unit 1015, and achannel state information (CSI) report control unit 1017. The receptionunit 105 includes a decoding unit 1051, a demodulation unit 1053, ademultiplexing unit 1055, a radio reception unit 1057, and a channelmeasurement unit 1059. The transmission unit 107 includes a coding unit1071, a modulation unit 1073, a multiplexing unit 1075, a radiotransmission unit 1077, and an uplink reference signal generation unit1079.

The higher layer processing unit 101 outputs uplink data (transportblocks) generated by a user operation or the like to the transmissionunit 107. In addition, the higher layer processing unit 101 performsprocessing in a medium access control (MAC) layer, a packet dataconvergence protocol (PDCP) layer, a radio link control (RLC) layer, anda radio resource control (RRC) layer. When performing carrieraggregation, the higher layer processing unit 101 has a function ofperforming control of physical layers for performingactivation/deactivation of a cell and a function of performing controlof a physical layer for managing transmission timing of uplink. Thehigher layer processing unit 101 has a function of instructingmeasurement to be calculated by the reception unit 105 and judgingwhether or not to report (transfer) a measurement result calculated bythe reception unit 105.

The radio resource control unit 1011 provided in the higher layerprocessing unit 101 manages various configuration information of theterminal device 1. The radio resource control unit 1011 generatesinformation to be arranged in each uplink channel and outputs theinformation to the transmission unit 107.

The subframe configuration unit 1013 provided in the higher layerprocessing unit 101 manages a subframe configuration in the base stationdevice 3 and/or a base station device different from the base stationdevice 3 based on information configured by the base station device 3.For example, the subframe configuration is an uplink or downlinkconfiguration for a subframe. The subframe configuration includes asubframe pattern configuration, an uplink-downlink configuration, anuplink reference UL-DL configuration (uplink reference configuration), adownlink reference UL-DL configuration (downlink referenceconfiguration), and/or a transmission direction UL-DL configuration(transmission direction configuration). The subframe configuration unit1013 sets the subframe configuration, the subframe patternconfiguration, the uplink-downlink configuration, the uplink referenceUL-DL configuration, the downlink reference UL-DL configuration, and/orthe transmission direction UL-DL configuration. In addition, thesubframe configuration unit 1013 is able to set at least two subframesets. Note that, the subframe pattern configuration includes an EPDCCHsubframe configuration. Note that, the subframe configuration unit 1013is also referred to as a terminal subframe configuration unit.

The scheduling information interpretation unit 1015 provided in thehigher layer processing unit 101 interprets a DCI format (schedulinginformation) received through the reception unit 105, generates controlinformation for controlling the reception unit 105 and the transmissionunit 107 based on a result of interpreting the DCI format, and outputsthe control information to the control unit 103.

Based on the subframe configuration, the subframe pattern configuration,the uplink-downlink configuration, the uplink reference UL-DLconfiguration, the downlink reference UL-DL configuration, and/or thetransmission direction UL-DL configuration, the scheduling informationinterpretation unit 1015 determines timings at which transmissionprocessing and reception processing are performed.

The CSI report control unit 1017 specifies a CSI reference resource. TheCSI report control unit 1017 instructs the channel measurement unit 1059to derive a CQI associated with the CSI reference resource. The CSIreport control unit 1017 instructs the transmission unit 107 to transmitthe CQI. The CSI report control unit 1017 sets a configuration used bythe channel measurement unit 1059 to calculate the CQI.

Based the control information from the higher layer processing unit 101,the control unit 103 generates a control signal that controls thereception unit 105 and the transmission unit 107. The control unit 103outputs the generated control signal to the reception unit 105 and thetransmission unit 107, and controls the reception unit 105 and thetransmission unit 107.

The reception unit 105, following the control signal input from thecontrol unit 103, demultiplexes, demodulates, and decodes a receptionsignal received from the base station device 3 via the transmit/receiveantenna 109. The reception unit 105 outputs the decoded information tothe higher layer processing unit 101.

The radio reception unit 1057 down-converts a downlink signal receivedvia the transmit/receive antenna 109 to an intermediate frequency,removes unnecessary frequency components, controls an amplificationlevel so that a signal level is suitably maintained, conducts orthogonaldemodulation based on in-phase components and orthogonal components ofthe received signal, and converts the orthogonally demodulated analogsignal into a digital signal. The radio reception unit 1057 removes aportion corresponding to a guard interval (GI) from the converteddigital signal, applies the Fast Fourier Transform (FFT) to the signalwith the guard interval removed, and extracts a signal in the frequencydomain.

The demultiplexing unit 1055 demultiplexes the extracted signal into thePHICH, the PDCCH, the EPDCCH, the PDSCH, and/or the downlink referencesignal. Moreover, the demultiplexing unit 1055 compensates channels ofthe PHICH, the PDCCH, the EPDCCH, and/or the PDSCH from estimatedchannel values input from the channel measurement unit 1059. Inaddition, the demultiplexing unit 1055 outputs the demultiplexeddownlink reference signal to the channel measurement unit 1059.

The demodulation unit 1053 multiplies the PHICH by a corresponding codeto combine, performs demodulation according to a BPSK (Binary PhaseShift Keying) modulation scheme for the combined signal, and outputs theresultant to the decoding unit 1051. The decoding unit 1051 decodes thePHICH addressed to the terminal device 1, and outputs a decoded HARQindicator to the higher layer processing unit 101. The demodulation unit1053 performs demodulation according to a QPSK modulation scheme for thePDCCH and/or the EPDCCH, and outputs the resultant to the decoding unit1051. The decoding unit 1051 attempts decoding of the PDCCH and/or theEPDCCH, and in the case of successful decoding, outputs decoded downlinkcontrol information and RNTI included in the downlink controlinformation to the higher layer processing unit 101.

The demodulation unit 1053 performs demodulation for the PDSCH accordingto a modulation scheme notified in the downlink grant, such as QPSK(Quadrature Phase Shift Keying), 16QAM (Quadrature AmplitudeModulation), or 64QAM, and outputs the resultant to the decoding unit1051. The decoding unit 1051 performs decoding based on informationrelated to a coding rate notified in the downlink control information,and outputs the decoded downlink data (transport blocks) to the higherlayer processing unit 101.

The channel measurement unit 1059 measures a downlink path loss and achannel state from the downlink reference signal input from thedemultiplexing unit 1055, and outputs the measured path loss and channelstate to the higher layer processing unit 101. In addition, the channelmeasurement unit 1059 calculates an estimated downlink channel valuefrom the downlink reference signal, and outputs the estimated value tothe demultiplexing unit 1055. The channel measurement unit 1059 performschannel measurement and/or interference measurement for calculation ofthe CQI. The channel measurement unit 1059 performs measurement to benotified to a higher layer from the downlink reference signal input fromthe demultiplexing unit 1055. The channel measurement unit 1059calculates RSRP and RSRQ and outputs the resultant to the higher layerprocessing unit 101.

The transmission unit 107, following a control signal input from thecontrol unit 103, generates an uplink reference signal, codes andmodulates uplink data (transport blocks) input from the higher layerprocessing unit 101, and multiplexes the PUCCH, the PUSCH, and thegenerated uplink reference signal, followed by transmission to the basestation device 3 via the transmit/receive antenna 109.

The coding unit 1071 codes uplink control information input from thehigher layer processing unit 101 by means of convolutional coding, blockcoding, or the like. In addition, the coding unit 1071 performs turbocoding based on information used for scheduling of the PUSCH.

The modulation unit 1073 modulates a coded bit input from the codingunit 1071 according to a modulation scheme notified in the downlinkcontrol information or a modulation scheme predetermined for eachchannel, such as BPSK, QPSK, 16QAM, or 64QAM. Based on information usedfor scheduling of the PUSCH, the modulation unit 1073 determines thenumber of data sequences to be spatially multiplexed, maps a pluralityof pieces of uplink data to be transmitted in the same PUSCH by usingMIMO SM (Multiple Input Multiple Output Spatial Multiplexing) to aplurality of sequences, and performs precoding for the sequences.

The uplink reference signal generation unit 1079 generates a sequenceobtained according to predetermined rules (formulas), based on aphysical layer cell identity (PCI; also referred to as a Cell ID) or thelike for identifying the base station device 3, a bandwidth in which theuplink reference signal is arranged, a cyclic shift notified in theuplink grant, values of parameters for generating a DMRS sequence, andthe like. The multiplexing unit 1075, following the control signal inputfrom the control unit 103, reorders the PUSCH modulation symbols inparallel and then applies the Discrete Fourier Transform (DFT). Inaddition, the multiplexing unit 1075 multiplexes the PUCCH and PUSCHsignals and the generated uplink reference signal for each transmitantenna port. That is, the multiplexing unit 1075 arranges the PUCCH andPUSCH signals and the generated uplink reference signal into resourceelements for each transmit antenna port.

The radio transmission unit 1077 applies the Inverse Fast FourierTransform (IFFT) to the multiplexed signal, performs modulationaccording to a SC-FDMA scheme, adds a guard interval to the SC-FDMAsymbols subjected to SC-FDMA modulation, generates a digital signal in abaseband, converts the digital signal in the baseband to an analogsignal, generates in-phase components and orthogonal components of anintermediate frequency from the analog signal, removes excess frequencycomponents from an intermediate frequency band, up-converts the signalof the intermediate frequency to a signal of high frequency, removesexcess frequency components, amplifies power, and outputs the resultantto the transmit/receive antenna 109 for transmission.

FIG. 8 is a schematic block diagram illustrating a configuration of thebase station device 3 of the present embodiment. As illustrated therein,the base station device 3 includes a higher layer processing unit 301, acontrol unit 303, a reception unit 305, a transmission unit 307, and atransmit/receive antenna 309. In addition, the higher layer processingunit 301 includes a radio resource control unit 3011, a subframeconfiguration unit 3013, a scheduling unit 3015, and a CSI reportcontrol unit 3017. In addition, the reception unit 305 includes adecoding unit 3051, a demodulation unit 3053, a demultiplexing unit3055, a radio reception unit 3057, and a channel measurement unit 3059.In addition, the transmission unit 307 includes a coding unit 3071, amodulation unit 3073, a multiplexing unit 3075, a radio transmissionunit 3077, and a downlink reference signal generation unit 3079.

The higher layer processing unit 301 performs processing in a mediumaccess control (MAC) layer, a packet data convergence protocol (PDCP)layer, a radio link control (RLC) layer, and a radio resource control(RRC) layer. In addition, the higher layer processing unit 301 generatescontrol information for controlling the reception unit 305 and thetransmission unit 307, and outputs the control information to thecontrol unit 303. The higher layer processing unit 301 has a function ofacquiring a reported (transferred) measurement result.

The radio resource control unit 3011 provided in the higher layerprocessing unit 301 generates, or acquires from a higher node, downlinkdata (transport blocks) to be arranged in the downlink PDSCH, systeminformation, an RRC message, and a MAC CE (control element), andperforms output to the transmission unit 307. In addition, the radioresource control unit 3011 manages various configuration information foreach terminal device 1.

The subframe configuration unit 3013 provided in the higher layerprocessing unit 301 performs management of a subframe configuration, asubframe pattern configuration, an uplink-downlink configuration, anuplink reference UL-DL configuration, a downlink reference UL-DLconfiguration, and/or a transmission direction UL-DL configuration foreach terminal device 1. The subframe configuration unit 3013 sets thesubframe configuration, the subframe pattern configuration, theuplink-downlink configuration, the uplink reference UL-DL configuration,the downlink reference UL-DL configuration, and/or the transmissiondirection UL-DL configuration to each terminal device 1. The subframeconfiguration unit 3013 transmits information related to the subframeconfiguration to the terminal device 1. Note that, the subframeconfiguration unit 3013 is also referred to as a base station subframeconfiguration unit.

The base station device 3 may determine the subframe configuration, thesubframe pattern configuration, the uplink-downlink configuration, theuplink reference UL-DL configuration, the downlink reference UL-DLconfiguration, and/or the transmission direction UL-DL configuration toeach terminal device 1. In addition, the subframe configuration, thesubframe pattern configuration, the uplink-downlink configuration, theuplink reference UL-DL configuration, the downlink reference UL-DLconfiguration, and/or the transmission direction UL-DL configuration toeach terminal device 1 may be instructed to the base station device 3from a higher node.

For example, the subframe configuration unit 3013 may determine thesubframe configuration, the subframe pattern configuration, theuplink-downlink configuration, the uplink reference UL-DL configuration,the downlink reference UL-DL configuration, and/or the transmissiondirection UL-DL configuration based on an uplink traffic amount and adownlink traffic amount.

The subframe configuration unit 3013 is able to manage at least twosubframe sets. The subframe configuration unit 3013 may set at least twosubframe sets to each terminal device 1. The subframe configuration unit3013 may set at least two subframe sets to each serving cell. Thesubframe configuration unit 3013 may set at least two subframe sets toeach CSI process. The subframe configuration unit 3013 is able totransmit information indicating at least two subframe sets to theterminal device 1 through the transmission unit 307.

The scheduling unit 3015 provided in the higher layer processing unit301 determines frequencies and subframes to which physical channels(PDSCH and PUSCH) are to be allocated, a coding rate and a modulationscheme of the physical channels (PDSCH and PUSCH), transmit power, andthe like from received channel state information, and estimated channelvalues and channel quality input from the channel measurement unit 3059.The scheduling unit 3015 determines whether to perform scheduling of adownlink physical channel and/or a downlink physical signal orscheduling of an uplink physical channel and/or an uplink physicalsignal in a flexible subframe. Based on a scheduling result, thescheduling unit 3015 generates control information (for example, DCIformat) for controlling the reception unit 305 and the transmission unit307, and outputs the control information to the control unit 303.

Based on a scheduling result, the scheduling unit 3015 generatesinformation used for scheduling of the physical channels (PDSCH andPUSCH). Based on the UL-DL configuration, the subframe patternconfiguration, the uplink-downlink configuration, the uplink referenceUL-DL configuration, the downlink reference UL-DL configuration, and/orthe transmission direction UL-DL configuration, the scheduling unit 3015determines timings (subframes) at which transmission processing andreception processing are performed.

The CSI report control unit 3017 provided in the higher layer processingunit 301 controls CSI report of the terminal device 1. The CSI reportcontrol unit 3017 transmits information indicating various configurationassumed for deriving a CQI in a CSI reference resource by the terminaldevice 1 to the terminal device 1 through the transmission unit 307.

Based the control information from the higher layer processing unit 301,the control unit 303 generates a control signal that controls thereception unit 305 and the transmission unit 307. The control unit 303outputs the generated control signal to the reception unit 305 and thetransmission unit 307, and controls the reception unit 305 and thetransmission unit 307.

The reception unit 305, following the control signal input from thecontrol unit 303, demultiplexes, demodulates, and decodes a receptionsignal received from the terminal device 1 via the transmit/receiveantenna 309, and outputs decoded information to the higher layerprocessing unit 301. The radio reception unit 3057 down-converts anuplink signal received via the transmit/receive antenna 309 to anintermediate frequency, removes unnecessary frequency components,controls an amplification level so that a signal level is suitablymaintained, performs orthogonal demodulation based on in-phasecomponents and orthogonal components of the received signal, andconverts the orthogonally demodulated analog signal into a digitalsignal.

The radio reception unit 3057 removes a portion corresponding to a guardinterval (GI) from the converted digital signal. The radio receptionunit 3057 applies the Fast Fourier Transform (FFT) to the signal withthe guard interval removed, extracts a signal in the frequency domain,and outputs the signal to the demultiplexing unit 3055.

The demultiplexing unit 1055 demultiplexes the signal input from theradio reception unit 3057 into signals such as the PUCCH, the PUSCH, andthe uplink reference signal. Note that, this demultiplexing is performedbased on radio resource allocation information included in an uplinkgrant which is determined by the radio resource control unit 3011 of thebase station device 3 in advance and notified to each terminal device 1.The demultiplexing unit 3055 compensates the channel of the PUCCH andPUSCH from an estimated channel value input from the channel measurementunit 3059. In addition, the demultiplexing unit 3055 outputs thedemultiplexed uplink reference signal to the channel measurement unit3059.

The demodulation unit 3053 applies the Inverse Discrete FourierTransform (IDFT) to the PUSCH, acquires modulation symbols, and for eachmodulation symbol in the PUCCH and the PUSCH, demodulates the receivedsignal by using a modulation scheme that is predetermined or notified inadvance by the base station device 3 to each terminal device 1 in theuplink grant, such as BPSK (binary phase shift keying), QPSK, 16QAM, or64QAM. The demodulation unit 3053 separates the modulation symbols in aplurality of pieces of uplink data transmitted on the same PUSCH byusing MIMO SM, based on the number of spatially multiplexed sequencesnotified in advance in the uplink grant to each terminal device 1, andinformation giving instructions on precoding to be performed for thesesequences.

The decoding unit 3051 decodes coded bits of the demodulated PUCCH andPUSCH according to a predetermined coding scheme at a coding rate thatis predetermined or notified in advance by the base station device 3 tothe terminal device 1 in the uplink grant, and outputs the decodeduplink data and uplink control information to the higher layerprocessing unit 101. In a case where the PUSCH is retransmitted, thedecoding unit 3051 performs decoding by using coded bits and demodulatedcoded bits that are held in a HARQ buffer input from the higher layerprocessing unit 301. The channel measurement unit 309 measures anestimated channel value, channel quality, and the like from the uplinkreference signal input from the demultiplexing unit 3055, and outputsthe resultant to the demultiplexing unit 3055 and the higher layerprocessing unit 301.

The transmission unit 307, following the control signal input from thecontrol unit 303, generates a downlink reference signal, codes andmodulates a HARQ indicator, downlink control information, and downlinkdata input from the higher layer processing unit 301, multiplexes thePHICH, the PDCCH, the EPDCCH, the PDSCH, and the downlink referencesignal, and transmits a signal to the terminal device 1 via thetransmit/receive antenna 309.

The coding unit 3071 codes a HARQ indicator, downlink controlinformation, and downlink data input from the higher layer processingunit 301 by using a predetermined coding scheme, such as block coding,convolutional coding, or turbo coding, or alternatively, performs codingby using a coding scheme determined by the radio resource control unit3011. The modulation unit 3073 modulates coded bits input from thecoding unit 3071 according to a modulation scheme that is predeterminedor determined by the radio resource control unit 3011, such as BPSK,QPSK, 16QAM, or 64QAM.

The downlink reference signal generation unit 3079 generates, as adownlink reference signal, a sequence known to the terminal device 1 andobtained according to predetermined rules based on a physical layer cellidentity (PCI) for identifying the base station device 3. Themultiplexing unit 3075 multiplexes the modulated modulation symbols ofeach channel and the generated downlink reference signal. That is, themultiplexing unit 3075 arranges the modulated modulation symbols of eachchannel and the generated downlink reference signal into resourceelements.

The radio transmission unit 3077 applies the Inverse Fast FourierTransform (IFFT) to the multiplexed modulation symbols and the like,performs modulation according to the OFDM scheme, adds a guard intervalto the OFDM modulated OFDM symbols, generates a digital signal in abaseband, converts the digital signal in the baseband to an analogsignal, generates in-phase components and orthogonal components of anintermediate frequency from the analog signal, removes excess frequencycomponents from the intermediate frequency band, up-converts the signalof intermediate frequency to a signal of high frequency, removes excessfrequency components, amplifies power, and outputs the resultant to thetransmit/receive antenna 309 for transmission.

Here, the PDCCH or the EPDCCH is used to notify (designate) downlinkcontrol information (DCI) to a terminal device. For example, thedownlink control information includes information about resourceallocation of the PDSCH, information about MCS (Modulation and Codingscheme), information about scrambling identity (also referred to asscrambling identifier), reference signal sequence identity (alsoreferred to as base sequence identity, base sequence identifier, or basesequence index), and the like.

A small cell will be described below. The small cell is a collectiveterm indicating a cell which is constituted by a base station devicewith less transmit power than that of a macro cell and has smallcoverage. Small cells are able to be operated being arranged denselybecause of being able to have smaller coverage. A base station device ina small cell is arranged at a place different from that of a basestation device in a macro cell. The small cells arranged densely aresynchronized with each other to be formed as a small cell cluster. Thecells in the small cell cluster are connected by backhaul (opticalfiber, X2 interface, S1 interface), and a technique of interferencesuppression, such as eICIC (enhanced Inter-Cell InterferenceCoordination), FeICIC (Further enhanced Inter-Cell InterferenceCoordination), or CoMP (Coordinated Multi-Point transmission/reception),is able to be applied in the small cells in the small cell cluster. Thesmall cell may be operated in a frequency band different from that ofthe macro cell. In particular, from a viewpoint of channel attenuation(path loss), by operating the small cell in a higher frequency band thanthat of the macro cell, it becomes easy to form the small cell withsmaller coverage.

The small cell operated in a different frequency band is operated byusing the macro cell and a carrier aggregation technique or a dualconnectivity technique.

Note that, the small cell may be operated at the same frequency as thatof the macro cell. The small cell may be operated out of the coverage ofthe macro cell. The base station device in the small cell may bearranged in the same place as that of the base station device in themacro cell.

The carrier aggregation technique will be described in detail below.

Dependently on capacity of a terminal device, a secondary cell isconfigured to form a serving cell set with a primary cell. The number ofdownlink component carriers configured to the terminal device needs tobe greater than or the same as the number of uplink component carriersconfigured to the terminal device, and only the uplink componentcarriers are not able to be configured as secondary cells.

The primary cell is always used for transmission of the PUCCH. In otherwords, PUCCH is not able to be transmitted in the secondary cell.

Reconfiguration/addition/deletion of the secondary cell are performed byRRC. When a new secondary cell is added, all system information neededfor the new secondary cell is transmitted by dedicated RRC signaling.That is, system information does not need to be directly obtained fromthe secondary cell by means of reporting in a connected mode.

When the carrier aggregation is configured, a mechanism ofactivation/deactivation of the secondary cell is supported. Theactivation/deactivation is not applied to the primary cell. When thesecondary cell is deactivated, the terminal device does not need toreceive the associated PDCCH or PDSCH, and is not able to performtransmission in associated uplink and does not need to perform CQImeasurement. To the contrary, when the secondary cell is deactivated,the terminal device needs to receive the PDSCH and the PDCCH and isexpected to be able to perform CQI measurement.

The mechanism of activation/deactivation is based on a combination ofMAC CE and a deactivation timer. The MAC CE transfers information onactivation or deactivation of the secondary cell with a bitmap. A bit towhich 1 is set indicates activation of the associated secondary cell,and, to the contrary, a bit to which 0 is set indicates deactivation ofthe associated secondary cell.

Even when the base station device does not transmit data, the terminaldevice in an idle state transmits a synchronization signal, a referencesignal, and broadcast information, such as PSS/SSS, CRS, PBCH, or SIB,for connecting to the base station device. Therefore, signals thereofcause inter-cell interference.

Then, by shifting the base station device from a start-up state to astop state, the inter-cell interference is suppressed.

The stop state of the cell/base station device is a state where thePSS/SSS, the CRS, the PBCH, the PDCCH, or the PDSCH is not transmitted.An example thereof include a state where the PSS/SSS has not beentransmitted for one half or more frame (five or more subframes). Notethat, the base station device, even in the stop state, may performreception processing at a reception unit of the base station device.

The start-up state of the cell/base station device is a state where atleast the PSS/SSS and the CRS are transmitted. An example thereofinclude a state where the PSS/SSS is transmitted during one half frame.

Whether or not to shift the base station device in the start-up state tothe stop state is determined, for example, based on a connected state ofthe terminal device, a data request situation of the terminal deviceconnected to the base station device, measurement information on aphysical layer from the terminal device, CSI information from theterminal device, or the like.

One example of procedure of shifting the base station device in thestart-up state to the stop state will be described.

A base station device (serving cell) to which a terminal device isconnected determines whether or not to be shifted to the stop state fromthe start-up state based on a connected state of the terminal device, adata situation of the terminal device, and measurement information ofthe terminal device. The base station device which has judged to beshifted to the stop state transmits information for shifting to the stopstate to a base station device in a neighbour cell and performspreparation for the stop of a cell. The determination of whether or notto shift the start-up state to the stop state and the transmission ofinformation for shifting to the stop state may not be performed in theserving cell, and the determination and the transmission may beperformed, for example, in MME (Mobility Management Entity) and S-GW(Serving Gateway). In the preparation for the stop of the cell, when theterminal device is connected to the base station device, an instructionto cause the terminal device to perform handover to the neighbour cell,an instruction to perform deactivation, or the like is performed. Theserving cell to which no terminal device is connected due to thepreparation for the stop of the cell is shifted from the start-up stateto the stop state.

When the terminal device communicates with the base station device inthe stop state, the base station device is shifted from the stop stateto the start-up state.

Whether or not to shift the base station device in the stop state to thestart-up state is determined based on, for example, an uplink referencesignal from the terminal device, cell detection information from theterminal device, measurement information on a physical layer of theterminal device, or the like.

One example of procedure of shifting a base station device in the stopstate to the start-up state based on measurement information on aphysical layer will be described.

A base station device (serving cell) to which a terminal device isconnected and a base station device (neighbour cell) in the stop stateshare a configuration of a DRS through backhaul. The serving cellnotifies the terminal device of the configuration of the DRS. Theneighbour cell transmits the DRS. The terminal device detects the DRStransmitted from the neighbour cell based on the configuration of theDRS notified by the serving cell. Moreover, the terminal device performsmeasurement of a physical layer with use of the DRS transmitted from theneighbour cell. The terminal device reports (transfers) a measurementresult to the serving cell. Based on the report of the measurementresult from the terminal device, the serving cell determines whether ornot to shift the base station device in the stop state to the start-upstate, and when determining to shift to the start-up state, notifies thebase station device in the stop state of information for instructingstart-up. Note that, the determination of whether or not to shift thestop state to the start-up state and the transmission of the informationfor instructing start-up may not be performed in the serving cell, andthe determination and the transmission may be performed, for example, inMME (Mobility Management Entity) and S-GW (Serving Gateway). Theneighbour cell receiving the information for instructing start-up isshifted from the stop state to the start-up state.

One example of procedure of shifting a base station device in the stopstate to the start-up state based on measurement information on aphysical layer will be described.

A base station device (serving cell) to which a terminal device isconnected and a base station device (neighbour cell) in the stop stateshare a configuration of an SRS of the terminal device through backhaul.The serving cell notifies the terminal device of the configuration ofthe SRS. The terminal device transmits the SRS based on theconfiguration of the SRS or an instruction of an SRS request. Theneighbour cell detects the SRS transmitted from the terminal device.Moreover, the neighbour cell performs measurement of a physical layerwith use of the SRS transmitted from the terminal device. Based on ameasurement result by the SRS, the neighbour cell determines whether ornot to shift the base station device to the start-up state and performsshift from the stop state to the start-up state. Note that, thedetermination of whether or not to shift the stop state to the start-upstate may not be performed in the neighbour cell, and the determinationand the transmission may be performed, for example, in a serving cell,MME (Mobility Management Entity), and S-GW (Serving Gateway). In thiscase, after performing measurement of the physical layer with use of theSRS, the neighbour cell transmits a measurement result to the servingcell, the MME, and the S-GW and receives information for instructingstart-up.

The serving cell may notify the terminal device of informationindicating a start-up/stop state of a neighbour cell. The terminaldevice recognizes the start-up state or the stop state of the cell tothereby switch behavior of the terminal device. An example of thebehavior of the terminal device includes a method for measuringinterference, or the like.

One example of a method for notifying information indicating astart-up/stop state of a cell will be described.

Information indicating a start-up/stop state of a target cell isnotified by L1 signaling (Layer 1 signaling). In other words, theinformation indicating the start-up/stop state of the target cell isnotified by the PDCCH or the EPDCCH. One bit corresponding to the targetcell is allocated, and 0 (false, disable) indicates stop and 1 (true,enable) indicates start-up. The bit corresponding to the target cell maybe constituted as a set of bitmaps so that the start-up/stop state isnotified simultaneously to a plurality of cells. Association of the bitwith the target cell is notified by dedicated RRC signaling.

The information indicating the start-up/stop state is notified by a DCIformat 1C. Note that, the information indicating the start-up/stop statemay be notified by a DCI format 3/3A. Note that, the informationindicating the start-up/stop state may be notified by a format havingthe same payload size as that of the DCI format 1C.

The information indicating the start-up/stop state is notified by ashared search space. The shared search space is a search space sharedbetween cells. In addition, the information indicating the start-up/stopstate is notified by a search space shared in a terminal group. Here,the search space shared in a terminal group is a search space in which astart point of CCE in which PDCCH candidates are arranged is determinedwith use of RNTI (UE-group C-RNTI, TP-specific-RNTI, SCE-RNTI) allocatedin the terminal group in a shared manner.

A notification period of the information indicating the start-up/stopstate is one radio frame unit. The notification period of theinformation indicating the start-up/stop state is configured bydedicated RRC signaling.

In the notification of the information indicating the start-up/stopstate, information on a next radio frame of the radio frame in which theL1 signaling is received is indicated. Note that, when the L1 signalingis received in the first subframe (subframe 0) within a radio frame,information on the radio frame in which the reception is performed maybe indicated.

One example of a method for notifying information indicating astart-up/stop d state of a cell will be described.

Information indicating a start-up/stop state of a target cell isnotified by a change in a configuration of the DRS. The configuration ofthe DRS when transmitted from the target cell becomes different betweenthe start-up state and the stop state.

The information indicating the start-up/stop state of the target cell isnotified by a specific example of a change of a configuration offollowing one or more DRSs. The DRS transmitted in the start-up stateand the DRS transmitted in the stop state are different in arrangementof a resource element. The DRS transmitted in the start-up state and theDRS transmitted in the stop state are different in an antenna port. TheDRS transmitted in the start-up state and the DRS transmitted in thestop state are different in a scramble sequence. The DRS transmitted inthe start-up state and the DRS transmitted in the stop state aredifferent in an initial value of the scramble sequence. The DRStransmitted in the start-up state and the DRS transmitted in the stopstate are different in transmit power. The DRS transmitted in thestart-up state and the DRS transmitted in the stop state are differentin a subframe period of transmission. The DRS transmitted in thestart-up state and the DRS transmitted in the stop state are differentin a transmission bandwidth or the number of resource blocks.

The terminal device monitors two patterns of the configuration of theDRS indicating the start-up state and the configuration of the DRSindicating the stop state. The terminal device monitors two patterns byusing a monitoring pattern for the configuration of the DRS indicatingthe start-up state and a monitoring pattern for the configuration of theDRS indicating the stop state. The terminal device implicitly acquiresinformation on the start-up/stop state of the target cell according tothe monitoring pattern by which the DRS is detected. The monitoringpattern for the configuration of the DRS indicating the start-up stateand the monitoring pattern for the configuration of the DRS indicatingthe stop state may be defined in advance. The monitoring pattern for theconfiguration of the DRS indicating the start-up state and themonitoring pattern for the configuration of the DRS indicating the stopstate may be notified from the base station device by dedicated RRCsignaling.

One example of a method for notifying information indicating astart-up/stop state of a cell will be described.

Information indicating a start-up/stop state of a target cell isnotified by a change in a configuration of the CRS. The configuration ofthe CRS transmitted from the target cell becomes different between thestart-up state and the stop state.

The information indicating the start-up/stop state of the target cell isnotified by a specific example of a change of following one or moreCRSs. The CRS transmitted in the start-up state and the CRS transmittedin the stop state are different in arrangement of a resource element.The CRS transmitted in the start-up state and the CRS transmitted in thestop state are different in an antenna port. The CRS transmitted in thestart-up state and the CRS transmitted in the stop state are differentin a scramble sequence. The CRS transmitted in the start-up state andthe CRS transmitted in the stop state are different in an initial valueof the scramble sequence. The CRS transmitted in the start-up state andthe CRS transmitted in the stop state are different in transmit power.The CRS transmitted in the start-up state and the CRS transmitted in thestop state are different in a subframe period of transmission. The CRStransmitted in the start-up state and the CRS transmitted in the stopstate are different in a transmission bandwidth or the number ofresource blocks.

The terminal device monitors two patterns of the configuration of theCRS indicating the start-up state and the configuration of the CRSindicating the stop state. The terminal device monitors two patterns byusing a monitoring pattern for the configuration of the CRS indicatingthe start-up state and a monitoring pattern for the configuration of theCRS indicating the stop state. The terminal device implicitly acquiresinformation on the start-up/stop state of the target cell according tothe monitoring pattern by which the CRS is detected. The monitoringpattern for the configuration of the CRS indicating the stop state maybe defined in advance. The monitoring pattern for the configuration ofthe CRS indicating the stop state may be notified from the base stationdevice by dedicated RRC signaling.

One example of a method for notifying information indicating astart-up/stop state of a cell will be described.

Information indicating a start-up/stop state of a cell is notified bydedicated RRC signaling. The information indicating the start-up/stopstate of the cell is notified as a list in association with a centerfrequency and a cell ID.

The terminal device is able to recognize a start-up/stop state of atarget cell with the aforementioned notification methods. Hereinafter,when behavior of the terminal device is switched according to thestart-up/stop state of the target cell, any of the aforementionednotification methods is applied.

Description will be given below for detection of a cell (base stationdevice).

Detection of a cell means detection of a synchronization signal and/or areference signal transmitted from a base station device constituting thecell by a terminal device. The synchronization signal and/or thereference signal used for detection of the cell include information on acell ID. The terminal device detects the cell based on the cell ID ofthe cell and a detection reference of the synchronization signal and/orthe reference signal.

One example of the detection reference of the synchronization signaland/or the reference signal will be described.

The terminal device determines detection based on intensity of receivepower and/or receive power quality of the synchronization signal and/orthe reference signal from the cell. The terminal device compares theintensity of receive power and/or the receive power quality of thesynchronization signal and/or the reference signal to a threshold, andwhen the reception intensity and/or the receive power quality isgreater, it is judged that the cell is detected. Examples of the receivepower intensity include RSRP and the like. Examples of the receptionquality include an amount of interference, RSRQ, SINR, and the like. Thedetection of the cell may be judged by a measurement event describedbelow.

One example of the detection reference for the synchronization signaland/or the reference signal will be described.

The terminal device determines detection based on success or failure indecoding of information of the synchronization signal and/or thereference signal from the cell. For example, the cell transmits a paritycode, such as CRC, to be carried on the synchronization signal and/orthe reference signal. The terminal device performs decoding by using theparity code included in the synchronization signal and/or the referencesignal, and when judging that the decoding is performed successfully bydetection of the parity, judges that the cell is detected.

After detecting the cell in the terminal device, the terminal deviceselects a cell to be connected/activated and select a cell to bedisconnected/deactivated.

Alternatively, after detecting the cell in the terminal device, theterminal device reports information on the detected cell to a connectedbase station device. The information on the detected cell includes acell ID and information on measurement.

Details of the CRS will be described below.

The CRS is transmitted by antenna ports 0-3.

The CRS is arranged in all downlink subframes which are non-MBSFNsubframes. In other words, the CRS is arranged in all downlink subframesother than MBSFN subframes.

A resource element and a signal sequence of the CRS are determined basedon a physical cell identity (PCI).

FIG. 10 illustrates a configuration of the CRS. A signal of the CRS isgenerated by using a pseudo-random number sequence. The pseudo-randomnumber sequence is, for example, a Gold sequence. The pseudo-randomnumber sequence is calculated based on a physical cell identity (PCI).The pseudo-random number sequence is calculated based on a type of CP.The pseudo-random number sequence is calculated based on a slot numberand an OFDM symbol number in a slot. As the resource element of the CRSin the case of normal CP, R0-3 of FIG. 10 are used. R0 indicatesarrangement of the CRS of an antenna port 0, R1 indicates arrangement ofthe CRS of an antenna port 1, R2 indicates arrangement of the CRS of anantenna port 2, and R3 indicates arrangement of the CRS of an antennaport 3. The resource element of the CRS transmitted by one antenna portis arranged in a period of six subcarriers on a frequency axis. Theresource element of the CRS transmitted by the antenna port 0 and theresource element of the CRS transmitted by the antenna port 1 arearranged to be separated from each other by three subcarriers. The CRSis cell-specifically shifted on the frequency based on a cell ID. Theresource elements of the CRS transmitted by the antenna port 0 and theCRS transmitted by the antenna port 1 are arranged in OFDM symbols 0 and4 in the case of normal CP, and arranged in OFDM symbols 0 and 3 in thecase of extended CP. The resource elements of the CRS transmitted by anantenna port 2 and the CRS transmitted by an antenna port 3 are arrangedin an OFDM symbol 1. The CRS is transmitted in a broadband with abandwidth configured in downlink.

Details of the DRS will be described below. The DRS is transmitted froma base station device for various purposes, such as synchronization of atime domain in downlink, synchronization of a frequency in downlink,specification of a cell/transmission point, measurement of RSRP,measurement of RSRQ, and measurement of a geographic position of aterminal device.

The DRS is transmitted in a downlink subframe. The DRS is transmitted ina downlink component carrier.

The DRS is transmitted when the base station device is in a stop state.Note that, the DRS may be transmitted even when the base station deviceis in a start-up state.

The DRS is periodically transmitted on a time axis. The DRS iscontinuously transmitted for configured subframes. For example, the DRSis continuously transmitted for N subframes in a period of M subframe.The period M in which the DRS is transmitted, the number of subframes Nto be continuously transmitted in the period, and a subframe L in whichthe DRS is arranged in the period are configured in a higher layer. Notethat, the number of subframes N to be continuously transmitted in theperiod may be defined in advance. When the subframe period M isconfigured to be long, the number of times of transmission by the basestation device in the stop state decreases, thus making it possible toreduce inter-cell interference. Note that, M, N, and L may be configureddifferently between the stop state and the start-up state fortransmission.

The DRS is transmitted by including information on a cell ID. Here, theinformation on the cell ID is information for identifying a cell inwhich the DRS is transmitted. Examples thereof include a physical cellID, CGI (Cell Global Identity), and a new cell identity (such as smallcell ID, discovery ID, or extended cell ID). Note that, a plurality ofIDs related to the cell may be transmitted by the DRS. For example, inan environment where the physical cell identity is insufficient for thenumber of cells to be arranged, the physical cell identity is able to besubstantially extended by transmitting the physical cell identity and anew cell identity in combination in the DRS.

The DRS is transmitted by antenna ports p, . . . , and p+n−1. Here, n isa total number of antenna ports for transmitting the DRS. Values of p, .. . , and p+n−1 are values other than 0 to 22 and 107 to 110.

One example of a configuration of the DRS will be described.

FIG. 9 illustrates one example of the configuration of the DRS. Asequence used by a signal of the DRS is generated by a Zadoff-Chusequence on a frequency axis. The DRS is contiguously arranged on thefrequency axis. The DRS uses six resource blocks and is transmitted byusing sixty-two subcarriers thereof. The DRS is transmitted with zeropower in ten subcarriers of the six resource blocks. In other words, theDRS reserves ten subcarriers of the six resource blocks and does nottransmit a signal therein. The DRS is arranged in the last OFDM symbolsof a slot 0 and a slot 10 in the case of the FDD (frame configurationtype 1) and are mapped to the third OFDM symbols of a subframe 1 and asubframe 6 in the case of the TDD (frame configuration type 2). The DRSis transmitted by including a part of information for specifying a cellID.

Note that, the DRS may be arranged in a resource block different fromthat of the PSS. The DRS may be transmitted by using the differentnumber of resource blocks from that of the PSS. The DRS may betransmitted by using the different number of subcarriers from that ofthe PSS. The DRS may be arranged in an OFDM symbol different from thatof the PSS. The DRS may be transmitted by including informationdifferent from that of the cell ID.

One example of a configuration of the DRS will be described.

FIG. 9 illustrates one example of the configuration of the DRS. Asequence used by a signal of the DRS is interleaved by connecting twobinary sequences having a length of 31. The sequence of the signal ofthe DRS is generated based on an M-sequence. In the DRS, a signalarranged in a subframe 0 is different from a signal arranged in asubframe 5. The DRS is arranged in sixth OFDM symbols of a slot 0 and aslot 10 in the case of the FDD and arranged in seventh OFDM symbols of aslot 1 and a slot 11 in the case of the TDD. In other words, the DRS isarranged in the second last OFDM symbols of the slot 0 and the slot 10in the case of the FDD and arranged in the last OFDM symbols of the slot1 and the slot 11 in the case of the TDD. The DRS may be transmitted byincluding a part of information for specifying a cell ID.

Note that, the DRS may be arranged in a resource block different fromthat of the SSS. The DRS may be transmitted by using the differentnumber of resource blocks from that of the SSS. The DRS may betransmitted by using the different number of subcarriers from that ofthe SSS. The DRS may be arranged in an OFDM symbol different from thatof the SSS. The DRS may be transmitted by including informationdifferent from that of the cell ID.

Note that, the number of subframes in which the DRS is transmitted isnot limited. For example, the DRS may be transmitted in subframes 0, 1,5, and 6. In this case, a large quantity of information is able to beincluded in the DRS for transmission. In this case, the number oforthogonal sequences increases, so that an effect of suppressinginter-cell interference is achieved.

One example of a configuration of the DRS will be described.

FIG. 10 illustrates one example of the configuration of the DRS. Asignal of the DRS is generated by using a pseudo-random number sequence.The pseudo-random number sequence is, for example, a Gold sequence. Thepseudo-random number sequence is calculated based on a cell ID. Thepseudo-random number sequence is calculated based on a type of CP. Thepseudo-random number sequence is calculated based on a slot number andan OFDM symbol number in a slot. A resource element of the DRStransmitted by one antenna port is arranged in a period of sixsubcarriers on a frequency axis. The resource element of the DRStransmitted by the antenna port p and the resource element of the DRStransmitted by the antenna port p+1 are arranged to be separated fromeach other by three subcarriers. The DRS is cell-specifically shifted onthe frequency based on a cell ID. The resource elements of the DRStransmitted by the antenna port p and the DRS transmitted by the antennaport p+1 are arranged in OFDM symbols 0 and 4 in the case of normal CP,and arranged in OFDM symbols 0 and 3 in the case of extended CP. Theresource elements of the DRS transmitted by an antenna port p+2 and theDRS transmitted by an antenna port p+3 are arranged in an OFDM symbol 1.The DRS is transmitted in a broadband with a bandwidth configured indownlink.

Note that, the DRS may use a pseudo-random number sequence differentfrom that of the CRS. The DRS may use a sequence calculation methoddifferent from that of the CRS. The DRS may be arranged on the frequencyin a period of frequency different from that of the CRS. An arrangementrelation between the resource elements of the antenna port p by whichthe DRS is transmitted and the antenna port p+1 by which the DRS istransmitted may be different from an arrangement relation of the antennaport 0 and the antenna port 1. The DRS may be shifted to be arranged onthe frequency based on information different from that of the CRS. TheDRS may be arranged in an OFDM symbol different from that of the CRS.The DRS may be arranged with a bandwidth different from that of the CRS,or may be arranged with a bandwidth configured in a higher layer to betransmitted in a narrow band.

One example of a configuration of the DRS will be described.

FIG. 11 illustrates one example of the configuration of the DRS. Asignal of the DRS is generated by using a pseudo-random number sequence.The pseudo-random number sequence is, for example, a Gold sequence. Thepseudo-random number sequence is calculated based on a cell ID. Thepseudo-random number sequence is calculated based on a type of CP. Thepseudo-random number sequence is calculated based on a slot number andan OFDM symbol number in a slot. The DRS transmitted by one antenna portis arranged in a period of six subcarriers on a frequency axis. The DRSis cell-specifically shifted on the frequency based on a cell ID. TheDRS is arranged in OFDM symbols 3, 5 and 6 of a slot 0 and OFDM symbols1, 2, 3, 5 and 6 of a slot 1 in the case of normal CP, and arranged inOFDM symbols 4 and 5 of the slot 0 and OFDM symbols 1, 2, 4, and 5 ofthe slot 1 in the case of extended CP. The resource elements of the DRSis arranged being shifted by L on the frequency between the I-th OFDMsymbol and the I+L-th OFDM symbol. The DRS is transmitted in a broadbandwith a bandwidth configured in downlink.

Note that, the DRS may use a pseudo-random number sequence differentfrom that of the PRS. The DRS may use a sequence calculation methoddifferent from that of the PRS. The DRS may be arranged on the frequencyin a period of a subcarrier different from that of the PRS. The DRS maybe arranged in an OFDM symbol different from that of the PRS. The DRSmay be arranged with a bandwidth different from that of the PRS, or maybe arranged with a bandwidth configured in a higher layer to betransmitted in a narrow band.

One example of a configuration of the DRS will be described.

FIG. 10 illustrates one example of the configuration of the DRS. Asignal of the DRS is generated by using a pseudo-random number sequence.The pseudo-random number sequence is, for example, a Gold sequence. Thepseudo-random number sequence is calculated based on information from ahigher layer. The pseudo-random number sequence is calculated based on acell ID when information from a higher layer is not configured. Thepseudo-random number sequence is calculated based on a type of CP. Thepseudo-random number sequence is calculated based on a slot number andan OFDM symbol number in a slot. A resource element in which the DRS isarranged is defined by a configuration number (DRS configuration) andcalculated by using a table of FIG. 12. In the table, k′ denotes asubcarrier number, l′ denotes an OFDM symbol number, n_(s) denotes aslot number, and n_(s) mod 2 denotes a slot number. For example, in thecase of a configuration number 0, the DRS is arranged in resourceelements of a slot number 0, a subcarrier number 9, and OFDM symbolnumbers 5 and 6. The DRS is transmitted in a broadband with a bandwidthconfigured in downlink.

Note that, the DRS may use a pseudo-random number sequence differentfrom that of the CSI-RS. The DRS may use a sequence calculation methoddifferent from that of the CSI-RS. Without limitation to the table ofFIG. 12, the DRS is able to be arranged in a resource element differentfrom that of the CSI-RS. The DRS may be arranged with a bandwidthdifferent from that of the CSI-RS, or may be arranged with a bandwidthconfigured in a higher layer to be transmitted in a narrow band.

One example of a configuration of the DRS will be described.

FIG. 10 illustrates one example of the configuration of the DRS. Aresource element in which the DRS is arranged is defined by aconfiguration number (DRS configuration) and calculated by using thetable of FIG. 12. In the table, k′ denotes a subcarrier number, l′denotes an OFDM symbol number, n_(s) denotes a slot number, and n_(s)mod 2 denotes a slot number. For example, in the case of a configurationnumber 0, the DRS is arranged in resource elements of a slot number 0, asubcarrier number 9, and OFDM symbol numbers 5 and 6. The DRS istransmitted in a broadband with a bandwidth configured in downlink. TheDRS may be transmitted with zero power in the configured resourceelement. In other words, the DRS does not transmit a signal in theconfigured resource element.

Note that, without limitation to the table of FIG. 12, the DRS is ableto be arranged in a resource element different from that of the CSI-IM.The DRS may be arranged with a bandwidth different from that of theCSI-IM, or may be arranged with a bandwidth configured in a higher layerto be transmitted in a narrow band.

Though the configurations of the DRS have been described as above,without limitation to the aforementioned examples, the DRS isconstituted by combination of the examples.

One example of preferable combinations is cited. The DRS is configuredby a combination of a signal constituted by the Zadoff-Chu sequence, asignal constituted based on the M-sequence, and a signal constitutedbased on the Gold sequence. The signal constituted based on the Goldsequence is constituted in a broadband compared to the signalconstituted by of the Zadoff-Chu sequence, the signal constituted by theZadoff-Chu sequence is transmitted with use of six resource blocks, andthe signal constituted based on the Gold sequence is transmitted in anentire band of a subframe.

One example of preferable combinations is cited. The DRS is configuredby a combination of a signal constituted by the Zadoff-Chu sequence, asignal constituted based on the M-sequence, a signal constituted basedon the Gold sequence, and a signal transmitted with zero power. Thesignal constituted based on the Gold sequence and the signal transmittedwith zero power specify resource elements based on a configurationinformation on the DRS. The signal constituted based on the Goldsequence is configured in a broadband compared to the signal constitutedby the Zadoff-Chu sequence, the signal constituted by the Zadoff-Chusequence is transmitted with use of six resource blocks, and the signalconstituted based on the Gold sequence is transmitted in an entire bandof a subframe.

A configuration of the DRS is notified to the terminal device bydedicated RRC signaling. The configuration of the DRS includesinformation shared between cells in which the RS is transmitted andinformation on each cell in which the DRS is transmitted. Note that, theconfiguration of the DRS may be notified being included in configurationinformation on a measurement object described below.

The information shared between cells in which the DRS is transmittedincludes information on a center frequency of a band, information on abandwidth, information on a subframe, and the like.

The information on each cell in which the DRS is transmitted includesinformation on a center frequency of a band, information on a bandwidth,information on a subframe, information for designating a resourceelement, information for specifying a cell (cell ID, PCI), and the like.

With the configuration of the DRS, the terminal device is able torecognize the subframe including the DRS and thus does not need toperform detection processing of the DRS in a subframe not including theDRS. This makes it possible to reduce power consumption of the terminaldevice.

Differences between the CRS and the DRS will be described below.

The CRS is arranged in all subframes other than MBSFN subframes. On theother hand, the DRS is arranged periodically in a subframe period whichis configured.

Thereby, the DRS has a low density of resource elements on the time axisand is able to suppress inter-cell interference compared to the CRS.

In the CRS, a resource element and a signal sequence are determinedbased on the physical cell identity (PCI). On the other hand, in theDRS, a resource element and a signal sequence are determined based on aparameter other than the physical cell identity (PCI). Examples of theparameter other than the physical cell identity (PCI) include CGI,extended cell ID, DRS configuration index, and the like.

Thereby, the DRS is able to be transmitted with more types than thephysical cell identity (PCI), and is therefore suitable for celldetection/identification in an environment where many cells are dense.

Details of measurement of a physical layer will be described below. Theterminal device performs measurement of a physical layer to be reportedto a higher layer. As the measurement of the physical layer, there areRSRP (Reference Signal Received Power), RSSI (Received Signal StrengthIndicator), RSRQ (Reference Signal Received Quality), and the like.

Details of the RSRP will be described below. The RSRP is defined asreceive power of a reference signal.

One example of the RSRP will be described.

The RSRP is defined as a value obtained by linearly averaging power ofresource elements in which the CRS included in a considered measurementfrequency bandwidth is transmitted. A resource element in which the CRSof an antenna port 0 is mapped is used to determine the RSRP. When theterminal device is able to detect the CRS of an antenna port 1, aresource element in which the CRS of the antenna port 1 is mapped isalso able to be used to determine the RSRP in addition to the resourceelement in which the CRS of the antenna port 0 is mapped. Hereinafter,the RSRP calculated by using the resource element in which the CRS ofthe antenna port 0 is mapped is referred to as a CRS-based RSRP or afirst RSRP.

The terminal device measures the RSRP of an intra-frequency cell and/oran inter-frequency cell in an RRC idle (RRC_IDLE) state. In this case,the intra-frequency cell in the RRC idle state is a cell having the samefrequency band as that of a cell in which system information is receivedwith broadcast by the terminal device. The inter-frequency cell in theRRC idle state is a cell having a frequency band different from that ofa cell in which system information is received with broadcast by theterminal device. The terminal device measures the RSRP of anintra-frequency cell and/or an inter-frequency cell in an RRC connected(RRC_CONNECTED) state. In this case, the intra-frequency cell in the RRCconnected state is a cell having the same frequency band as that of acell in which system information is received with RRC signaling orbroadcast by the terminal device. The inter-frequency cell in the RRCconnected state is a cell having a frequency band different from that ofa cell in which system information is received with RRC signalingbroadcast by the terminal device.

One example of the RSRP will be described.

The RSRP is defined as a value obtained by linearly averaging power ofresource elements in which the CSI-RS included in a consideredmeasurement frequency bandwidth is transmitted. A resource element inwhich the CSI-RS is mapped is used to determine the RSRP. The resourceelement and the antenna port by which the CSI-RS is transmitted arenotified in a higher layer. Hereinafter, the RSRP calculated by using aresource element different from the resource element used for the firstRSRP is referred to as a RSRP or a second RSRP.

The terminal device measures the RSRP of the intra-frequency cell and/orthe inter-frequency cell in the RRC connected (RRC_CONNECTED) state.

One example of the RSRP will be described.

The RSRP is defined as a value obtained by linearly averaging power ofresource elements in which the PSS included in a considered measurementfrequency bandwidth is transmitted. A resource element in which the PSSis mapped is used to determine the RSRP.

The terminal device measures the RSRP of the intra-frequency cell and/orthe inter-frequency cell in the RRC idle (RRC_IDLE) state. Moreover, theterminal device measures the RSRP of the intra-frequency cell and/or theinter-frequency cell in the RRC connected (RRC_CONNECTED) state.

One example of the RSRP will be described.

The RSRP is defined as a value obtained by linearly averaging power ofresource elements in which the PSS and the SSS included in a consideredmeasurement frequency bandwidth are transmitted. A resource element inwhich the PSS and the SSS are mapped is used to determine the RSRP.

The terminal device measures the RSRP of the intra-frequency cell and/orthe inter-frequency cell in the RRC idle (RRC_IDLE) state. Moreover, theterminal device measures the RSRP of the intra-frequency cell and/or theinter-frequency cell in the RRC connected (RRC_CONNECTED) state.

One example of the RSRP will be described.

The RSRP is defined as a value obtained by linearly averaging power ofresource elements in which the DRS included in a considered measurementfrequency bandwidth is transmitted. A resource element in which the DRSis mapped is used to determine the RSRP. The resource element and theantenna port by which the DRS is transmitted are notified in a higherlayer.

The terminal device measures the RSRP of the intra-frequency cell and/orthe inter-frequency cell in the RRC connected (RRC_CONNECTED) state.

One example of the RSRP will be described.

The RSRP is defined as a value obtained by linearly averaging power ofresource elements in which the CRS or the DRS included in a consideredmeasurement frequency bandwidth is transmitted. To determine the RSRP, aresource element in which the DRS is mapped is used when a configurationfrom a higher layer is performed, and a resource element in which theCRS of the antenna port 0 is mapped is used when the configuration isnot performed from a higher layer. In a case where the terminal deviceis able to detect the CRS of the antenna port 1 when the configurationis not performed from a higher layer, a resource element in which theCRS of the antenna port 1 is mapped is also able to be used to determinethe RSRP in addition to the resource element in which the CRS of theantenna port 0 is mapped. The resource element and the antenna port bywhich the DRS is transmitted are notified in the higher layer.

Here, one example of the configuration from the higher layer includeswhether or not a configuration of the DRS (DRS-Config) is performed.

Alternatively, as one example of the configuration from the higherlayer, a measurement result to be reported is configured in associationwith a parameter to be designated. For example, the configuration isperformed in association with a new parameter (report Quantity) includedin a report configuration (report Config).

One example of the RSRP will be described.

The RSRP is defined as a value obtained by linearly averaging power ofresource elements in which the CRS or the DRS included in a consideredmeasurement frequency bandwidth is transmitted. To determine the RSRP, aresource element in which the DRS is mapped is used when informationindicating a stop state of a target cell is received, and a resourceelement in which the CRS of the antenna port 0 is mapped is used wheninformation indicating a start-up state of a target cell is received. Ina case where the terminal device is able to detect the CRS of theantenna port 1 when the information indicating the start-up state of thetarget cell is received, a resource element in which the CRS of theantenna port 1 is mapped is also able to be used to determine the RSRPin addition to the resource element in which the CRS of the antenna port0 is mapped. The resource element and the antenna port by which the DRSis transmitted are notified in a higher layer.

The terminal device measures the RSRP of the intra-frequency cell and/orthe inter-frequency cell in the RRC connected (RRC_CONNECTED) state.

One example of the RSRP will be described.

The RSRP is defined as a value obtained by linearly averaging power ofresource elements in which the CRS or the DRS included in a consideredmeasurement frequency bandwidth is transmitted. To determine the RSRP, aresource element in which the DRS is mapped is used when the DRS isdetected, and a resource element in which the CRS of the antenna port 0is mapped is used when the DRS is not detected. In a case where theterminal device is able to detect the CRS of the antenna port 1 when theconfiguration is not performed from a higher layer, a resource elementin which the CRS of the antenna port 1 is mapped is also able to be usedto determine the RSRP in addition to the resource element in which theCRS of the antenna port 0 is mapped. The resource element and theantenna port by which the DRS is transmitted are notified in a higherlayer.

A reference as to whether or not the DRS is detected is, for example,comparison of receive power of the resource element in which the DRS ismapped to a reference value.

The reference as to whether or not the DRS is detected is, for example,comparison of receive power of the resource element in which the DRS ismapped to receive power of the resource element in which the CRS of theantenna port 0 is mapped.

Note that, when the DRS is not transmitted in the start-up state, a cellto be measured switches a type of the RSRP between the start-up stateand the stop state.

Details of the RSSI will be described below. The RSSI is defined bytotal receive power observed by using a receive antenna.

One example of the RSSI will be described.

The RSSI (E-UTRA carrier RSSI) is formed by a value obtained by linearlyaveraging total receive power obtained from observation of only OFDMsymbols assumed to include a reference signal to the antenna port 0. Inother words, the RSSI is formed by a value obtained by linearlyaveraging total receive power obtained from observation of only OFDMsymbols assumed to include the CRS of the antenna port 0. The RSSI isobserved in a bandwidth of N resource blocks. The total receive power ofthe RSSI includes power from a serving cell or a non-serving cell of thesame channel, interfering power from an adjacent channel, thermal noisepower, and the like.

One example of the RSSI will be described.

The RSSI (E-UTRA carrier RSSI) is formed by a value obtained by linearlyaveraging total receive power obtained from observation of all OFDMsymbols. The total receive power of the RSSI includes power from aserving cell or a non-serving cell of the same channel, interferingpower from an adjacent channel, thermal noise power, and the like.

One example of the RSSI will be described.

The RSSI (E-UTRA carrier RSSI) is formed by a value obtained by linearlyaveraging total receive power obtained from observation of only resourceelements including the DRS. The RSSI is observed in a bandwidth of Nresource blocks. The total receive power of the RSSI includes power froma serving cell or a non-serving cell of the same channel, interferingpower from an adjacent channel, thermal noise power, and the like. Theresource element and the antenna port by which the DRS is transmittedare notified in a higher layer.

Here, the RSSI may be measured by using the resource element in whichthe signal of the DRS is transmitted. In this case, the resource elementcalculated by the second RSRP is the same as the resource element of theRSSI. Arrangement information of the resource element in which the DRSis transmitted is configured to the terminal device.

Moreover, the RSSI may be measured by using the resource element of theDRS to be transmitted with zero power. In this case, the resourceelement calculated by the second RSRP is different from the resourceelement of the RSSI. Both of arrangement information of the resourceelement for calculating the second RSRP and arrangement information ofthe resource element for calculating the RSSI are configured to theterminal device.

Details of the RSRQ will be described below. The RSRQ is defined by aratio of the RSRP and the RSSI and is used for the purpose equivalent toa signal to interference noise ratio (SINR) of a cell to be measured,which is an index of communication quality. Though a combination of theRSRP and the RSSI is not limited to the following, a preferablecombination of the RSRP and the RSSI in the present embodiment will bedescribed.

One example of the RSRQ will be described.

The RSRQ is defined as a ratio calculated with a formula of N×RSRP/RSSI.In the formula, N denotes the number of resource blocks of a measurementbandwidth of the RSSI, and a numerator and a denominator of the RSRQneed to be constituted by the same set of resource blocks. In theformula, the RSRP is the first RSRP. The RSRQ calculated by using theRSRQ calculated with the first RSRP is referred to as CRS-based RSRQ orfirst RSRQ.

The RSSI (E-UTRA carrier RSSI) is formed by a value obtained by linearlyaveraging total receive power obtained from observation of only OFDMsymbols including a reference signal to the antenna port 0. In otherwords, the RSSI is formed by a value obtained by linearly averagingtotal receive power obtained from observation of only OFDM symbolsincluding the CRS of the antenna port 0. The RSSI is observed in abandwidth of N resource blocks. The total receive power of the RSSIincludes power from a serving cell or a non-serving cell of the samechannel, interfering power from an adjacent channel, thermal noisepower, and the like. When a predetermined subframe for performingmeasurement of the RSRQ is designated from signaling of a higher layer,the RSSI is measured from all OFDM symbols in the designated subframe.

The terminal device measures the RSRQ of an intra-frequency cell and/oran inter-frequency cell in the RRC idle state. The terminal devicemeasures the RSRQ of an intra-frequency cell and/or an inter-frequencycell in the RRC connected state.

One example of the RSRQ will be described.

The RSRQ is defined as a ratio calculated with a formula of N×RSRP/RSSI.In the formula, N denotes the number of resource blocks of a measurementbandwidth of the RSSI, and a numerator and a denominator of the RSRQneed to be constituted by the same set of resource blocks. In theformula, the RSRP is the second RSRP. The RSRQ calculated by using theRSRQ calculated with the second RSRP is referred to as a second RSRQ.

The RSSI (E-UTRA carrier RSSI) is formed by a value obtained by linearlyaveraging total receive power obtained from observation of only OFDMsymbols assumed to include a reference signal to the antenna port 0. Inother words, the RSSI is formed by a value obtained by linearlyaveraging total receive power obtained from observation of only OFDMsymbols including the CRS of the antenna port 0. The RSSI is observed ina bandwidth of N resource blocks. The total receive power of the RSSIincludes power from a serving cell or a non-serving cell of the samechannel, interfering power from an adjacent channel, thermal noisepower, and the like. When a predetermined subframe for performingmeasurement of the RSRQ is designated from signaling of a higher layer,the RSSI is measured from all OFDM symbols in the designated subframe.

The terminal device measures the RSRQ of the intra-frequency cell and/orthe inter-frequency cell in the RRC connected state.

One example of the RSRQ will be described.

Though each example of the RSRQ has been described above, a definitionof the RSRQ may change depending on the situation. For example, accuracyof the RSSI varies greatly between the start-up state and the stopstate.

The RSRQ is defined as a ratio calculated with a formula ofN×RSRP/(RSSI+N×RSRP) when a target cell is in the stop state andcalculated with a formula of N×RSRP/RSSI when the target cell is in thestart-up state. In the formulas, N denotes the number of resource blocksof a measurement bandwidth of the RSSI, and a numerator and adenominator of the RSRQ need to be constituted by the same set ofresource blocks. In the formulas, the RSRP is the second RSRP.

The RSSI (E-UTRA carrier RSSI) is formed by a value obtained by linearlyaveraging total receive power obtained from observation of only OFDMsymbols assumed to include a reference signal to the antenna port 0. Inother words, the RSSI is formed by a value obtained by linearlyaveraging total receive power obtained from observation of only OFDMsymbols including the CRS of the antenna port 0. The RSSI is observed ina bandwidth of N resource blocks. The total receive power of the RSSIincludes power from a serving cell or a non-serving cell of the samechannel, interfering power from an adjacent channel, thermal noisepower, and the like. When a predetermined subframe for performingmeasurement of the RSRQ is designated from signaling of a higher layer,the RSSI is measured from all OFDM symbols in the designated subframe.

One example of the RSRQ will be described.

The RSRQ is defined as a ratio calculated with a formula of N×RSRP/RSSI.In the formula, N denotes the number of resource blocks of a measurementbandwidth of the RSSI, and a numerator and a denominator of the RSRQneed to be constituted by the same set of resource blocks. In theformula, the RSRP is the second RSRP.

The RSSI (E-UTRA carrier RSSI) is formed by a value obtained by linearlyaveraging total receive power obtained from observation of only resourceelements including the DRS. The RSSI is observed in a bandwidth of Nresource blocks. The total receive power of the RSSI includes power froma serving cell or a non-serving cell of the same channel, interferingpower from an adjacent channel, thermal noise power, and the like. Whena predetermined subframe for performing measurement of the RSRQ isdesignated from signaling of a higher layer, the RSSI is measured fromthe designated subframe. The resource element and the antenna port bywhich the DRS is transmitted are notified in a higher layer.

One example of the RSRQ will be described.

Though each example of the RSRQ has been described above, a definitionof the RSRQ may change depending on the situation. For example, accuracyof the RSSI varies greatly between the start-up state and the stopstate.

The RSRQ is defined as a ratio calculated with a formula ofN×RSRP/(RSSI+N×RSRP) when a configuration from a higher layer isperformed and calculated with a formula of N×RSRP/RSSI when theconfiguration is not performed from a higher layer. In the formulas, Ndenotes the number of resource blocks of a measurement bandwidth of theRSSI, and a numerator and a denominator of the RSRQ need to beconstituted by the same set of resource blocks. In the formulas, thefirst RSRP or the second RSRP is used for the RSRP based on theconfiguration from the higher layer.

The RSSI (E-UTRA carrier RSSI) is formed by a value obtained by linearlyaveraging total receive power obtained from observation of only OFDMsymbols assumed to include a reference signal to the antenna port 0. Inother words, the RSSI is formed by a value obtained by linearlyaveraging total receive power obtained from observation of only OFDMsymbols including the CRS of the antenna port 0. The RSSI is observed ina bandwidth of N resource blocks. The total receive power of the RSSIincludes power from a serving cell or a non-serving cell of the samechannel, interfering power from an adjacent channel, thermal noisepower, and the like. When a predetermined subframe for performingmeasurement of the RSRQ is designated from signaling of the higherlayer, the RSSI is measured from all OFDM symbols in the designatedsubframe.

Here, one example of the configuration from the higher layer includeswhether or not a configuration of the DRS (DRS-Config) is performed.

Alternatively, as one example of the configuration from the higherlayer, a measurement result to be reported is configured in associationwith a parameter to be designated. For example, the configuration isperformed in association with a new parameter (report Quantity) includedin a report configuration (report Config).

One example of DL RS TX power (Downlink reference signal transmit power)will be described.

The DL RS TX power is determined as a value obtained by linearlyaveraging power of resource elements delivering the CRS transmitted by abase station device which operates a system bandwidth.

One example of the DL RS TX power will be described.

The DL RS TX power is determined as a value obtained by linearlyaveraging power of resource elements delivering the DRS transmitted bythe base station device which operates the system bandwidth.

First measurement procedure will be described. The first measurement ismeasurement of the first RSRP and the first RSRQ.

The terminal device recognizes the resource element, in which the CRStransmitted by the antenna port 0 is arranged, from the physical cellidentity (PCI). The terminal device then measures the first RSRP fromthe resource element in which the CRS transmitted by the antenna port 0is arranged. Note that, the number of subframes used for the measurementis not limited, and the measurement may be performed over a plurality ofsubframes to report an average value. Next, the terminal devicerecognizes the OFDM symbol in which the antenna port 0 is included andmeasures the RSSI. Then, the terminal device calculates the first RSRQfrom the first RSRP and the RSSI. Note that, subframes used for themeasurement of the first RSRP and the RSSI may be different.

Hereinafter, a result obtained based on the first measurement procedure(first RSRP, first RSRQ) is referred to as a first measurement result.

Second measurement procedure will be described. The second measurementis measurement of the second RSRP and the second RSRQ.

The terminal device recognizes the resource element, in which the DRS isarranged, from configuration information on the DRS. The terminal devicethen measures the second RSRP from the resource element in which the DRSis arranged. Note that, the number of subframes used for the measurementis not limited, and the measurement may be performed over a plurality ofsubframes to report an average value. Next, the terminal device measuresthe RSSI. Then, the terminal device calculates the second RSRQ from thesecond RSRP and the RSSI.

Hereinafter, a result obtained based on the second measurement procedure(second RSRP, second RSRQ) is referred to as a second measurementresult.

Differences between the first RSRP/RSRQ and the second RSRP/RSRQ will bedescribed below.

The first RSRP/RSRQ is measured based on the CRS. On the other hand, thesecond RSRP/RSRQ is measured based on the RS other than the CRS. Anexample of the RS other than the CRS includes the DRS.

Thereby, a base station device to which the CRS is not transmitted isalso able to measure the RSRP/RSRQ.

The first RSRP may be measured by using any subframe. On the other hand,since the second RSRP is measured based on the RS arranged periodically,a subframe for measurement is implicitly designated. Specifically, thesecond RSRP is measured based on information on the subframe in whichthe RS is arranged, which is notified from the base station device.

Thereby, the terminal device does not need to perform monitoring formeasurement in all subframes, thus making it possible to reduce powerconsumption.

The physical cell identity is required to measure the first RSRP/RSRQ.On the other hand, information other than the physical cell identity isalso required to measure the second RSRP. Other information isconfiguration information on the RS, and examples thereof includeinformation for notifying the resource element in which the RS isarranged and information for notifying the number of antenna ports usedfor measurement.

Since the first RSRP/RSRQ is able to be measured when the terminaldevice recognizes the physical cell identity, the measurement isperformed in the RRC idle state and the RRC connected state. On theother hand, with respect to the second RSRP/RSRQ, the terminal deviceneeds also information other than the physical cell identity and otherinformation is notified by RRC signaling, so that the measurement isperformed only in the RRC connected state.

The terminal device of the present embodiment is a terminal devicecommunicating with a base station device, including: a reception unitwhich performs first measurement based on a first RS (CRS) and performssecond measurement based on a second RS (DRS); and a higher layerprocessing unit which reports a result of the first measurement and aresult of the second measurement to the base station device, in whichthe first measurement is performed in a first state and the firstmeasurement or the second measurement is performed in a second state.Both of the first measurement and the second measurement may beperformed in the second state, and only the second measurement may beperformed in the second state.

As one example, the first state is a state where configurationinformation on the second RS is not notified and the second state is astate where configuration information on the second RS is notified fromthe base station device. Further, as one example, the first state is astate where information on the second measurement is not configured andthe second state is a state where information on the second measurementis configured from the base station device. In addition, as one example,the second state is a state where the first RS is not transmitted.

The terminal device of the present embodiment is a terminal devicecommunicating with a base station device, including: a reception unitwhich performs first measurement when a predetermined cell is in a firststate and performs second measurement when the predetermined cell is ina second state; and a higher layer processing unit which reports thefirst measurement and the second measurement to the base station device,in which the first measurement and the second measurement are switchedbased on information indicating the first state/the second state of thepredetermined cell.

As one example, the information indicating the first state/the secondstate of the predetermined cell is notified from the base stationdevice. Further, as one example, the information indicating the firststate/the second state of the predetermined cell is notified by a changeof a configuration of a RS transmitted from the predetermined cell.

As one example, calculation is performed with a calculation formula of afirst RSRQ in the first measurement and calculation is performed with acalculation formula of a second RSRQ in the second measurement. Further,as one example, the first measurement is performed based on a CRS andthe second measurement is performed based on a RS different from theCRS.

A mechanism for reporting (transferring) a measurement value obtained bymeasurement of the terminal device to a higher layer will be describedbelow.

A model of measurement will be described. FIG. 13 illustrates a model ofmeasurement.

A measurement unit 1301 includes a layer 1 filtering unit 13011, a layer3 filtering unit 13012, and a report reference evaluation unit 13013.Note that, the measurement unit 1301 includes a part of functions of thereception unit 105 and the higher layer processing unit 101.Specifically, the layer 1 filtering 13011 is included in the receptionunit 105, and the layer 3 filtering 13012 and the report referenceevaluation 13013 are included in the higher layer processing unit 101.

A measurement value (sample) input from a physical layer is filtered bythe layer 1 filtering unit 13011. To the layer 1 filtering unit 13011,for example, an average of a plurality of input values, a weightedaverage, an average following channel characteristics, and the like areapplied, or other filtering methods may be applied. The measurementvalue reported from a layer 1 is input to the layer 1 filtering unit13011 and then to a layer 3. The measurement value input to the layer 3filtering unit 13012 is filtered. A configuration of the layer 3filtering is provided from RRC signaling. A period in which filtering bythe layer 3 filtering unit 13012 is performed and a report is performedis the same as an input measurement period. The report referenceevaluation unit 13013 checks whether the report of the measurement valueis actually required. An evaluation is based on one or more measurementflows. An example thereof includes comparison between differentmeasurement values. The terminal device performs evaluation of a reportreference each time at least a new measurement result is reported. Aconfiguration of the report reference is provided by RRC signaling.After it is judged that the report of the measurement value is requiredby the evaluation of the report reference, the terminal device transmitsmeasurement report information (measurement report message) by radiointerface.

Next, description will be given for measurement. The base station devicetransmits a measurement configuration message to the terminal device byusing an RRC connection reconfiguration message of RRC signaling (radioresource control signal). The terminal device configures systeminformation included in the measurement configuration message andperforms measurement, event evaluation, and measurement report for aserving cell and a neighbour cell (including a listed cell and/or adetected cell) in accordance with the notified system information. Thelisted cell is a cell listed in a measurement object (cells notified ina neighbour cell list from the base station device to the terminaldevice) and the detected cell is a cell detected by the terminal deviceon frequency indicated by a measurement object and not listed in themeasurement object (cells detected by the terminal device itself and notnotified in the neighbour cell list).

There are three types of measurements (intra-frequency measurements,inter-frequency measurements, and inter-radio access technologymeasurements (inter-RAT measurements)). The intra-frequency measurementsmean measurements at a downlink frequency of the serving cell (downlinkfrequency). The inter-frequency measurements mean measurements at afrequency different from the downlink frequency of the serving cell. Theinter-radio access technology measurements (inter-RAT measurements) meanmeasurements with a wireless technology (e.g., UTRA, GERAN, or CDMA2000)different from the wireless technology of the serving cell (e.g.,EUTRA).

The measurement configuration message includes addition and/ormodification and/or deletion of configurations of a measurement identity(meas Id), measurement objects, and reporting configurations, and aquantity configuration (quantity Config), a measurement gapconfiguration (meas Gap Config), a serving cell quality threshold(s-Measure), and the like.

The quantity configuration (quantity Config) specifies a layer 3filtering coefficient (L3 filtering coefficient) when the measurementobject is EUTRA. The layer 3 filtering coefficient (L3 filteringcoefficient) prescribes a ratio (rate) between the latest measurementresult and a previous filtering measurement result. The filtering resultis utilized for the event evaluation in the terminal device.

The measurement gap configuration (meas Gap Config) is utilized forcontrolling a configuration of a measurement gap pattern andactivation/deactivation of a measurement gap. In the measurement gapconfiguration (meas Gap Config), a gap pattern, a start system framenumber (start SFN), and a start subframe number are notified asinformation in the case of activating the measurement gap. The gappattern prescribes which pattern is used as the measurement gap. Thestart system frame number (start SFN) prescribes SFN (System FrameNumber) for starting the measurement gap. The start subframe numberprescribes a subframe number for starting the measurement gap.

The serving cell quality threshold (s-Measure) represents a thresholdrelated to quality of a serving cell and is utilized for controllingwhether or not the terminal device needs to perform measurement. Theserving cell quality threshold (s-Measure) is configured as a value forthe RSRP.

The measurement identity (meas Id) is utilized for linking themeasurement objects with the reporting configurations and specificallylinks a measurement object identity (meas Object Id) with a reportingconfiguration identity (report Config Id). The measurement identity(meas Id) is associated with one measurement object identity (measObject Id) and one reporting configuration identity (report Config Id).The measurement configuration message is able to beadded/modified/deleted in terms of relationships with the measurementidentity (meas Id), the measurement objects, and the reportingconfigurations.

Meas Object To Remove List is a command for deleting a specifiedmeasurement object identity (meas Object Id) and measurement objectscorresponding to the specified measurement object identity (meas ObjectId). In this case, all the measurement identities (meas Id) associatedwith the specified measurement object identity (meas Object Id) aredeleted. This command is able to specify a plurality of measurementobject identities (meas Object Id) at the same time.

Meas Object To Add Modify List is a command for modifying a specifiedmeasurement object identity (meas Object Id) for specified measurementobjects or for adding a specified measurement object identity (measObject Id) and specified measurement objects. This command is able tospecify a plurality of measurement object identities (meas Object Id) atthe same time.

Report Config To Remove List is a command for deleting a specifiedreporting configuration identity (report Config Id) and reportingconfigurations corresponding to the specified reporting configurationidentity (report Config Id). In this case, all the measurementidentities (meas Id) associated with the specified reportingconfiguration identity (report Config Id) are deleted. This command isable to specify a plurality of reporting configuration identities(report Config Id) at the same time.

Meas Id To Remove List is a command for deleting a specified measurementidentity (meas Id). In this case, the measurement object identity (measObject Id) and the reporting configuration identity (report Config Id)associated with the specified measurement identity (meas Id) are notdeleted and are maintained. This command is able to specify a pluralityof measurement identities (meas Id) at the same time.

Meas Id To Add Modify List is a command for modifying a specifiedmeasurement identity (meas Id) to be associated with a specifiedmeasurement object identity (meas Object Id) and a specified reportingconfiguration identity (report Config Id) or for associating a specifiedmeasurement object identity (meas Object Id) and a specified reportingconfiguration identity (report Config Id) with a specified measurementidentity (meas Id) to add the specified measurement identity (meas Id).This command is able to specify a plurality of measurement identities(meas Id) at the same time.

The measurement objects are prescribed for each radio access technology(RAT) and each frequency. The reporting configurations includeprescriptions for EUTRA and prescriptions for RAT other than EUTRA.

The measurement objects include a measurement object EUTRA (meas ObjectEUTRA) associated with a measurement object identity (meas Object Id).

The measurement object identity (meas Object Id) is an identity used foridentifying the configuration of the measurement objects. Theconfiguration of the measurement objects is prescribed for each radioaccess technology (RAT) and frequency as described above. Themeasurement objects are separately specified for EUTRA, UTRA, GERAN, andCDMA2000. The measurement object EUTRA (meas Object EUTRA), which is ameasurement object for EUTRA, prescribes information applied toneighbour cells of EUTRA. In the measurement object EUTRA (meas ObjectEUTRA), one having a different frequency is handled as a differentmeasurement object and is separately allocated with a measurement objectidentity (meas Object Id).

One example of information on a measurement object will be described.

The measurement object EUTRA (meas Object EUTRA) includes EUTRA carrierfrequency information (eutra-Carrier Info), a measurement bandwidth(measurement Bandwidth), antenna port 1 presence information(presenceAntennaPort1), an offset frequency (offset Freq), informationrelated to a neighbour cell list, and information related to a blacklist.

Next, information included in the measurement object EUTRA (meas ObjectEUTRA) will be described. The EUTRA carrier frequency information(eutra-Carrier Info) specifies a carrier frequency to be a measurementobject. The measurement bandwidth (measurement Bandwidth) indicates ameasurement bandwidth common to all the neighbour cells operating in thecarrier frequency to be the measurement object. The antenna port 1presence information (presenceAntennaPort1) indicates whether or not theantenna port 1 is used in a cell to be the measurement object. Theoffset frequency (offset Freq) indicates a measurement offset valueapplied to the frequency to be the measurement object.

One example of information on the measurement object will be described.

A configuration different from that of the first measurement isperformed to perform the second measurement.

The measurement object EUTRA (meas Object EUTRA) includes EUTRA carrierfrequency information (eutra-Carrier Info), a measurement bandwidth(measurement Bandwidth), DRS configuration information (DS configurationinformation, discovery signal measurement configuration information), anoffset frequency (offset Freq), information related to a neighbour celllist, and information related to a black list.

Next, information included in the measurement object EUTRA (meas ObjectEUTRA) will be described. The EUTRA carrier frequency information(eutra-Carrier Info) specifies a carrier frequency to be a measurementobject. The measurement bandwidth (measurement Bandwidth) indicates ameasurement bandwidth common to all the neighbour cells operating in thecarrier frequency to be the measurement object. The DRS configurationinformation is used to notify the terminal device of configurationinformation common in a frequency band required to detect the DRSconfiguration, and indicates, for example, a subframe number and asubframe period for transmission in a cell to be the measurement object.The offset frequency (offset Freq) indicates a measurement offset valueapplied to the frequency to be the measurement object.

One example of information related to a neighbour cell list and a blacklist will be described.

The information related to the neighbour cell list includes informationrelated to neighbour cells that are to be objects of the eventevaluation and the measurement report. The information related to theneighbour cell list includes a physical cell identity (physical cellID), a cell individual offset (cell Individual Offset; indicting ameasurement offset value applied to a neighbour cell), and the like. Inthe case of EUTRA, this information is utilized as information forperforming addition, modification, or deletion in the neighbour celllist already acquired by the terminal device from broadcast information(broadcasted system information).

The information related to the black list includes information relatedto neighbour cells that are not to be objects of the event evaluation orthe measurement report. The information related to the black listincludes a physical cell identity (physical cell ID) and the like. Inthe case of EUTRA, this information is utilized as information forperforming addition, modification, or deletion in the black cell list(black listed cell list) already acquired by the terminal device frombroadcast information.

One example of information related to a neighbour cell list and a blacklist will be described.

When the second measurement is performed, usage in a case where aphysical cell identity (PCI) is insufficient is assumed. Thus, a newneighbour cell list and a new black list in which the physical cellidentity is extended are required.

Information related to the new neighbour cell list (neighbour small celllist) includes information related to neighbour cells that are to beobjects of the event evaluation and the measurement report. Theinformation related to the new neighbour cell list includes a cell ID, acell individual offset (cell Individual Offset; indicting a measurementoffset value applied to a neighbour cell), cell individual DRSconfiguration information, and the like. The cell individual DRSconfiguration information is DRS information that is cell-specificallyconfigured, and an example thereof includes information indicating aresource element of the DRS to be used. In the case of EUTRA, theinformation is utilized as information for performing addition,modification, or deletion in the new neighbour cell list alreadyacquired by the terminal device from broadcast information (broadcastedsystem information).

The information related to the new black list includes informationrelated to neighbour cells that are not to be objects of the eventevaluation or the measurement report. The information related to the newblack list includes a cell ID and the like. In the case of EUTRA, thisinformation is utilized as information for performing addition,modification, or deletion in the new black cell list (black listed smallcell list) already acquired by the terminal device from broadcastinformation.

In this case, the cell ID is, for example, a physical cell identity(physical cell ID), CGI (Cell Global Identity), or a discovery ID, andis formed based on information on cell (transmission point) ID, which istransmitted by the DRS.

Details of the layer 3 filtering (Layer 3 filtering) will be describedbelow.

The terminal device filters a measurement result with a followingformula before using for the evaluation of the report reference and thereport of the measurement.

F _(n)=(1−α)×F _(n-1) +α×M _(n)

In the formula, M_(n) denotes a latest measurement result received froma physical layer, F_(n) denotes an updated measurement result after thefilter, which is used for the evaluation of the report reference or thereport of the measurement, and F_(n-1) denotes a measurement resultafter the previous filtering, and M₁ is set to F₀ when the firstmeasurement result is received from the physical layer, α=1/2^((k/4)),and k is a filtering coefficient with respect to a correspondingmeasurement amount.

By applying the filter, the terminal device keeps time property even fora different period of the input. The filtering coefficient k assumes asample period which is the same as 200 ms.

When k is set as 0, the layer 3 filtering is not applied.

The filtering is performed with the same domain as a domain used for theevaluation of the report reference or the report of the measurement. Forexample, filtering of a logarithm is performed for a measurement valueof a logarithm.

The period for the input to the filter is able to be configured freely.

When the reported measurement result and the previously reportedmeasurement result are obtained by different measurement methods, themeasurement result after the previous filter is reset. As the differentmeasurement methods, for example, there is a case where the reportedmeasurement result M_(n) is the second measurement result. In this case,the measurement result after the previous filter is reset. That is,M_(n) is set to F_(n-1). Alternatively, a formula of F_(n)=M_(n) isapplied instead of the formula of the filter.

Next, details of reporting configurations will be described.

The reporting configurations include reporting configuration EUTRA(report Config EUTRA) corresponding to a reporting configurationidentity (report Config Id), and the like.

The reporting configuration identity (report Config Id) is an identityused for identifying the reporting configurations related to themeasurement. The reporting configurations related to the measurementinclude prescriptions for EUTRA and prescriptions for RAT other thanEUTRA (UTRA, GERAN, CDMA2000) as described above. The reportingconfiguration EUTRA (report Config EUTRA) serving as reportingconfigurations for EUTRA defines triggering criteria of an eventutilized for reporting the measurement in EUTRA.

The reporting configuration EUTRA (report Config EUTRA) includes anevent identity (event Id), a triggering quantity (trigger Quantity),hysteresis, a time to trigger (time To Trigger), a reporting quantity(report Quantity), a maximum reporting cell number (max Report Cells), areporting interval (report Interval), and a reporting amount (reportAmount).

The event identity (event Id) is utilized for selecting criteria relatedto event triggered reporting. The event triggered reporting is a methodfor reporting the measurements when the event triggering criteria aresatisfied. In addition, there is also event triggered periodic reportingfor reporting the measurement a certain number of times at regularintervals when the event triggering criteria are satisfied.

When the event triggering criteria specified by the event identity(event Id) are satisfied, the terminal device performs the measurementreport to the base station device. The triggering quantity (triggerQuantity) is a quantity utilized for evaluating the event triggeringcriteria. That is, RSRP or RSRQ is specified. In other words, theterminal device utilizes a quantity specified by the triggering quantity(trigger Quantity) to perform the measurement of a downlink referencesignal and determines whether or not the event triggering criteriaspecified by the event identity (event Id) are satisfied. The hysteresisis a parameter utilized in the event triggering criteria. The time totrigger (time To Trigger) indicates a period in which the eventtriggering criteria are to be satisfied. The reporting quantity (reportQuantity) indicates a quantity reported in the measurement report. Inthis case, a quantity specified by the triggering quantity (triggerQuantity), or the RSRP and the RSRQ are specified. The maximum reportingcell number (max Report Cells) indicates the maximum number of cellsincluded in the measurement report. The reporting interval (reportInterval) is utilized for the periodical reporting or the eventtriggered periodic reporting and the reporting is periodically performedat intervals indicated by the reporting interval (report Interval). Thereporting amount (report Amount) prescribes the number of times of theperiodical reporting as needed.

Threshold parameters and offset parameters utilized in the eventtriggering criteria described below are notified to the terminal devicetogether with the event identity (event Id) in the reportingconfiguration.

The base station device notifies the serving cell quality threshold(s-Measure) in some cases and not in other cases. When the base stationdevice notifies the serving cell quality threshold (s-Measure), theterminal device performs the measurement of a neighbour cell and theevent evaluation (whether or not the event triggering criteria aresatisfied, also referred to as the evaluation of reporting criteria)when the RSRP of the serving cell is lower than the serving cell qualitythreshold (s-Measure). On the other hand, when the base station devicedoes not notify the serving cell quality threshold (s-Measure), theterminal device performs the measurement of a neighbour cell and theevent evaluation regardless of the RSRP of the serving cell.

Next, details of an event and event triggering criteria will bedescribed.

The terminal device satisfying the event triggering criteria transmits ameasurement report to the base station device. The measurement reportincludes a measurement result.

A plurality of event triggering criteria for performing the measurementreport are defined, and each of them has an entering condition and aleaving condition. That is, the terminal device satisfying an enteringcondition for the event specified by the base station device transmits ameasurement report to the base station device. On the other hand, theterminal device satisfying an event entering condition and transmittinga measurement report stops the transmission of the measurement reportwhen satisfying an event leaving condition.

In one example of an event and event triggering criteria describedbelow, either the first measurement result or the second measurementresult is used.

One example of the event will be described.

The event is triggered when a measurement result of a serving cell isbetter than a threshold. When satisfying a condition A1-1, the terminaldevice performs transmission of a measurement report thereof. Whensatisfying a condition A1-2, the terminal device stops the transmissionof the measurement report.

Entering condition A1-1: Ms-Hys>Threshold

Leaving condition A1-2: Ms+Hys<Threshold

Here, Ms denotes the first measurement result or the second measurementresult for the serving cell (a measurement offset value specific to thecell is not considered), Hys denotes a hysteresis parameter for thetarget event, and Threshold denotes a threshold parameter utilized forthe target event.

One example of the event will be described.

The event is triggered when a measurement result of a serving cell isworse than a threshold. When satisfying a condition A2-1, the terminaldevice performs transmission of a measurement report thereof. Whensatisfying a condition A2-2, the terminal device stops the transmissionof the measurement report.

Entering condition A2-1: Ms-Hys<Threshold

Leaving condition A2-2: Ms+Hys>Threshold

Here, Ms denotes the first measurement result or the second measurementresult for the serving cell (a measurement offset value specific to thecell is not considered), Hys denotes a hysteresis parameter for thetarget event, and Threshold denotes a threshold parameter utilized forthe target event.

One example of the event will be described.

The event is triggered when a measurement result of a neighbour cell isbetter than a measurement result of a primary cell. When satisfying acondition A3-1, the terminal device performs transmission of ameasurement report thereof. When satisfying a condition A3-2, theterminal device stops the transmission of the measurement report.

Entering condition A3-1: Mn+Ofn+Ocn-Hys>Mp+Ofp+Ocp+Off

Leaving condition A3-2: Mn+Ofn+Ocn+Hys<Mp+Ofp+Ocp+Off

Here, Mn denotes the first measurement result or the second measurementresult for the neighbour cell (a measurement offset value specific tothe cell is not considered), Ofn denotes a frequency-specificmeasurement offset value for a frequency of the neighbour cell, Ocndenotes a cell-specific measurement offset value for the neighbour cell(0 is set when not configured to the neighbour cell), Mp denotes thefirst measurement result or the second measurement result for theprimary cell (a measurement offset value specific to the cell is notconsidered), Ofp denotes a frequency-specific measurement offset valuefor a frequency of the primary cell, Ocp denotes a cell-specificmeasurement offset value for the primary cell (0 is set when notconfigured to the primary cell), Hys denotes a hysteresis parameter forthe target event, and Off denotes an offset parameter utilized for thetarget event.

One example of the event will be described.

The event is triggered when a measurement result of a neighbour cell isbetter than a threshold. When satisfying a condition A4-1, the terminaldevice performs transmission of a measurement report thereof. Whensatisfying a condition A4-2, the terminal device stops the transmissionof the measurement report.

Entering condition A4-1: Mn+Ofn+Ocn-Hys>Threshold

Leaving condition A4-2: Mn+Ofn+Ocn+Hys<Threshold

Here, Mn denotes the first measurement result or the second measurementresult for the neighbour cell (a measurement offset value specific tothe cell is not considered), Ofn denotes a frequency-specificmeasurement offset value for a frequency of the neighbour cell, Ocndenotes a cell-specific measurement offset value for the neighbour cell(0 is set when not configured to the neighbour cell), Hys denotes ahysteresis parameter for the target event, and Threshold denotes athreshold parameter utilized for the target event.

One example of the event will be described.

The event is triggered when a measurement result of a primary cell isworse than a threshold 1 and a measurement result of a neighbour cell isbetter than a threshold 2. When satisfying a condition A5-1 and acondition A5-2, the terminal device performs transmission of ameasurement report thereof. When satisfying a condition A5-3 and acondition A5-4, the terminal device stops the transmission of themeasurement report.

Entering condition A5-1: Mp-Hys<Threshold 1

Entering condition A5-2: Mn+Ofn+Ocn-Hys>Threshold 2

Leaving condition A5-3: Mp+Hys>Threshold 1

Leaving condition A5-4: Mn+Ofn+Ocn+Hys<Threshold 2

Here, Mp denotes the first measurement result or the second measurementresult for the primary cell (a measurement offset value specific to thecell is not considered), Mn denotes the first measurement result or thesecond measurement result for the neighbour cell (a measurement offsetvalue specific to the cell is not considered), Ofn denotes afrequency-specific measurement offset value for a frequency of theneighbour cell, Ocn denotes a cell-specific measurement offset value forthe neighbour cell (0 is set when not configured to the neighbour cell),Hys denotes a hysteresis parameter for the target event, and each ofThreshold 1 and Threshold 2 denotes a threshold parameter utilized forthe target event.

One example of the event will be described.

The event is triggered when a measurement result of a secondary cell isbetter than a measurement result of a neighbour cell. When satisfying acondition A6-1, the terminal device performs transmission of ameasurement report thereof. When satisfying a condition A6-2, theterminal device stops the transmission of the measurement report.

Entering condition A6-1: Mn+Ocn-Hys>Ms+Ocs+Off

Leaving condition A6-2: Mn+Ocn+Hys<Ms+Ocs+Off

Here, Mn denotes the first measurement result or the second measurementresult for the neighbour cell (a measurement offset value specific tothe cell is not considered), Ocn denotes a cell-specific measurementoffset value for the neighbour cell (0 is set when not configured to theneighbour cell), Ms denotes the first measurement result or the secondmeasurement result for the serving cell (a measurement offset valuespecific to the cell is not considered), Ocs denotes a cell-specificmeasurement offset value for the serving cell (0 is set when notconfigured to the neighbour cell), Hys denotes a hysteresis parameterfor the target event, and Off denotes an offset parameter utilized forthe target event.

In each example of the event and the event triggering criteria describedabove, the event triggering criteria are evaluated by using either thefirst measurement result or the second measurement result. Thus, it isrequired to specify which of the first measurement result and the secondmeasurement result is to be used.

One example of a method for specifying a type of the measurement resultutilized for evaluating the event triggering criteria will be describedbelow.

By the report configuration, the type of the measurement result utilizedfor evaluating the event triggering criteria is specified. The eventtriggering criteria are evaluated by using either the first measurementresult or the second measurement result according to a parameter.

As one specific example, the first measurement result or the secondmeasurement result is specified according to a trigger quantity (triggerQuantity). As the trigger quantity, four selection fields of {firstRSRP, first RSRQ, second RSRP, and second RSRQ} are prescribed. Theterminal device performs measurement of a downlink reference signal byusing a quantity specified by the trigger quantity (trigger Quantity)and judges whether or not to satisfy the event triggering criteriaspecified by the event identity (event Id).

As one specific example, as to whether to be the first measurementresult or the second measurement result, a new parameter for specifyingthe type of the measurement result utilized for evaluating the eventtriggering criteria (trigger Meas type) is prescribed in addition to thetrigger quantity. Information indicating to evaluate the eventtriggering criteria by using the first measurement result or informationindicating to evaluate the event triggering criteria by using the secondmeasurement result is set to the parameter. For example, when theinformation indicating to evaluate the event triggering criteria byusing the second measurement result is set to the parameter, theterminal device performs the second measurement and evaluates the eventtriggering criteria by using the second measurement result. Note that,the parameter may be used in common with a parameter for specifying atype of the measurement result to be reported (report Meas Type).

In the event triggering criteria using two or more measurement resultsfor one conditional expression, for example, when comparing ameasurement result of a serving cell to the measurement result of aneighbour cell, the type of the measurement result utilized forevaluating the event triggering criteria may be specified for each ofthem. For example, a new parameter used for the measurement result ofthe serving cell (trigger Meas TypeServ) and a new parameter used forthe measurement result of the neighbour cell (trigger Meas TypeNeigh)may be prescribed.

One example of a method for specifying the type of the measurementresult utilized for evaluating the event triggering criteria will bedescribed below.

By the report configuration, the type of the measurement result utilizedfor evaluating the event triggering criteria is specified depending onthe condition for specifying the measurement.

As one specific example, the type of the measurement result utilized forevaluating the event triggering criteria is determined depending on astart-up/stop state of a target cell. For example, when the target cellis in the start-up state, the event triggering criteria are evaluated byusing the first measurement result, and when the target cell is in thestop state, the event triggering criteria are evaluated by using thesecond measurement result.

As one specific example, the type of the measurement result utilized forevaluating the event triggering criteria is determined depending ondetection of reference signals. For example, when the CRS is detectedand the DRS is not detected, the event triggering criteria are evaluatedby using the first measurement result, and when the CRS is not detectedand the DRS is detected, the event triggering criteria are evaluated byusing the second measurement result. When both of the CRS and the DRSare detected, the event triggering criteria are evaluated by using themeasurement result having higher receive power. When neither the CRS northe DRS is detected, the event triggering criteria are not evaluated.

In each example of the event and the event triggering criteria describedbelow, both of the first measurement result and the second measurementresult are used.

One example of the event will be described.

The event is triggered when a measurement result of a serving cell isbetter than a threshold. When satisfying a condition C1-1 and acondition C1-1′, the terminal device performs transmission of ameasurement report thereof. When satisfying a condition C1-2 and acondition C1-2′, the terminal device stops the transmission of themeasurement report.

Entering condition C1-1: Ms-Hys>Threshold

Leaving condition C1-2: Ms+Hys<Threshold

Entering condition C1-1′: Ms′-Hys′>Threshold′

Leaving condition C1-2′: Ms′+Hys′<Threshold′

Here, Ms denotes the first measurement result for the serving cell (ameasurement offset value specific to the cell is not considered), Ms′denotes the second measurement result for the serving cell (ameasurement offset value specific to the cell is not considered), Hysdenotes a hysteresis parameter for the first measurement result withrespect to the target event, Hys′ denotes a hysteresis parameter for thesecond measurement result with respect to the target event, Thresholddenotes a threshold parameter utilized for the first measurement resultwith respect to the target event, and Threshold′ denotes a thresholdparameter utilized for the second measurement result with respect to thetarget event.

One example of the event will be described.

The event is triggered when a measurement result of a serving cell isworse than a threshold. When satisfying a condition C2-1 and a conditionC2-1′, the terminal device performs transmission of a measurement reportthereof. When satisfying a condition C2-2 and a condition C2-2′, theterminal device stops the transmission of the measurement report.

Entering condition C2-1: Ms-Hys<Threshold

Leaving condition C2-2: Ms+Hys>Threshold

Entering condition C2-1′: Ms′-Hys′<Threshold′

Leaving condition C2-2′: Ms′+Hys′>Threshold′

Here, Ms denotes the first measurement result for the serving cell (ameasurement offset value specific to the cell is not considered), Ms′denotes the second measurement result for the serving cell (ameasurement offset value specific to the cell is not considered), Hysdenotes a hysteresis parameter for the first measurement result withrespect to the target event, Hys′ denotes a hysteresis parameter for thesecond measurement result with respect to the target event, Thresholddenotes a threshold parameter utilized for the first measurement resultwith respect to the target event, and Threshold′ denotes a thresholdparameter utilized for the second measurement result with respect to thetarget event.

One example of the event will be described.

The event is triggered when a measurement result of a neighbour cell isbetter than a measurement result of a primary cell. When satisfying acondition C3-1 and a condition C3-1′, the terminal device performstransmission of a measurement report thereof. When satisfying acondition C3-2 and a condition C3-2′, the terminal device stops thetransmission of the measurement report.

Entering condition C3-1: Mn+Ofn+Ocn-Hys>Mp+Ofp+Ocp+Off

Leaving condition C3-2: Mn+Ofn+Ocn+Hys<Mp+Ofp+Ocp+Off

Entering condition C3-1′: Mn′+Ofn′+Ocn′-Hys′>Mp′+Ofp′+Ocp′+Off′

Leaving condition C3-2′: Mn′+Ofn′+Ocn′+Hys′<Mp′+Ofp′+Ocp′+Off′

Here, Mn denotes the first measurement result for the neighbour cell (ameasurement offset value specific to the cell is not considered), Mn′denotes the second measurement result for the neighbour cell (ameasurement offset value specific to the cell is not considered), Ofndenotes a frequency-specific measurement offset value for the firstmeasurement result with respect to a frequency of the neighbour cell,Ofn′ denotes a frequency-specific measurement offset value for thesecond measurement result with respect to a frequency of the neighbourcell, Ocn denotes a cell-specific measurement offset value for the firstmeasurement result with respect to the neighbour cell (0 is set when notconfigured to the neighbour cell), Ocn′ denotes a cell-specificmeasurement offset value for the second measurement result with respectto the neighbour cell (0 is set when not configured to the neighbourcell), Mp denotes the first measurement result for the primary cell (ameasurement offset value specific to the cell is not considered), Mp′denotes the second measurement result for the primary cell (ameasurement offset value specific to the cell is not considered), Ofpdenotes a frequency-specific measurement offset value for the firstmeasurement result with respect to a frequency of the primary cell, Ofp′denotes a frequency-specific measurement offset value for the secondmeasurement result with respect to a frequency of the primary cell, Ocpdenotes a cell-specific measurement offset value for the firstmeasurement result with respect to the primary cell (0 is set when notconfigured to the primary cell), Ocp′ denotes a cell-specificmeasurement offset value for the second measurement result with respectto the primary cell (0 is set when not configured to the primary cell),Hys denotes a hysteresis parameter for the first measurement result withrespect to the target event, Hys′ denotes a hysteresis parameter for thesecond measurement result with respect to the target event, Off denotesan offset parameter utilized for the first measurement result withrespect to the target event, and Off′ denotes an offset parameterutilized for the second measurement result with respect to the targetevent.

One example of the event will be described.

The event is triggered when a measurement result of a neighbour cell isbetter than a threshold. When satisfying a condition C4-1 and acondition C4-1′, the terminal device performs transmission of ameasurement report thereof. When satisfying a condition C4-2 and acondition C4-2′, the terminal device stops the transmission of themeasurement report.

Entering condition C4-1: Mn+Ofn+Ocn-Hys>Threshold

Leaving condition C4-2: Mn+Ofn+Ocn+Hys<Threshold

Entering condition C4-1′: Mn′+Ofn′+Ocn′-Hys′>Threshold′

Leaving condition C4-2′: Mn′+Ofn′+Ocn′+Hys′<Threshold′

Here, Mn denotes the first measurement result for the neighbour cell (ameasurement offset value specific to the cell is not considered), Mn′denotes the second measurement result for the neighbour cell (ameasurement offset value specific to the cell is not considered), Ofndenotes a frequency-specific measurement offset value for the firstmeasurement result with respect to a frequency of the neighbour cell,Ofn′ denotes a frequency-specific measurement offset value for thesecond measurement result with respect to a frequency of the neighbourcell, Ocn denotes a cell-specific measurement offset value for the firstmeasurement result with respect to the neighbour cell (0 is set when notconfigured to the neighbour cell), Ocn′ denotes a cell-specificmeasurement offset value for the second measurement result with respectto the neighbour cell (0 is set when not configured to the neighbourcell), Hys denotes a hysteresis parameter for the first measurementresult with respect to the target event, Hys′ denotes a hysteresisparameter for the second measurement result with respect to the targetevent, Threshold denotes a threshold parameter utilized for the firstmeasurement result with respect to the target event, and Thresholddenotes a threshold parameter utilized for the second measurement resultwith respect to the target event.

One example of the event will be described.

The event is triggered when a measurement result of a primary cell isworse than a threshold 1 and a measurement result of a neighbour cell isbetter than a threshold 2. When satisfying a condition C5-1, a conditionC5-2, a condition C5-1′, and a condition C5-2′, the terminal deviceperforms transmission of a measurement report thereof. When satisfying acondition C5-3, a condition C5-4, a condition C5-3′, and a conditionC5-4′, the terminal device stops the transmission of the measurementreport.

Entering condition C5-1: Mp-Hys<Threshold 1

Entering condition C5-2: Mn+Ofn+Ocn-Hys>Threshold 2

Leaving condition C5-3: Mp+Hys>Threshold 1

Leaving condition C5-4: Mn+Ofn+Ocn+Hys>Threshold 2

Entering condition C5-1′: Mp′-Hys′<Threshold 1′

Entering condition C5-2′: Mn′+Ofn′+Ocn′-Hys′>Threshold 2′

Leaving condition C5-3′: Mp′+Hys′>Threshold 1′

Leaving condition C5-4′: Mn′+Ofn′+Ocn′+Hys′<Threshold 2′

Here, Mp denotes the first measurement result for the primary cell (ameasurement offset value specific to the cell is not considered), Mp′denotes the second measurement result for the primary cell (ameasurement offset value specific to the cell is not considered), Mndenotes the first measurement result for the neighbour cell (ameasurement offset value specific to the cell is not considered), Mn′denotes the second measurement result for the neighbour cell (ameasurement offset value specific to the cell is not considered), Ofndenotes a frequency-specific measurement offset value for the firstmeasurement result with respect to a frequency of the neighbour cell,Ofn′ denotes a frequency-specific measurement offset value for thesecond measurement result with respect to a frequency of the neighbourcell, Ocn denotes a cell-specific measurement offset value for the firstmeasurement result with respect to the neighbour cell (0 is set when notconfigured to the neighbour cell), Ocn′ denotes a cell-specificmeasurement offset value for the second measurement result with respectto the neighbour cell (0 is set when not configured to the neighbourcell), Hys denotes a hysteresis parameter for the first measurementresult with respect to the target event, Hys′ denotes a hysteresisparameter for the second measurement result with respect to the targetevent, each of Threshold 1 and Threshold 2 denotes a threshold parameterutilized for the first measurement result with respect to the targetevent, and each of Threshold 1′ and Threshold 2′ denotes a thresholdparameter utilized for the second measurement result with respect to thetarget event.

One example of the event will be described.

The event is triggered when a measurement result of a secondary cell isbetter than a measurement result of a neighbour cell. When satisfying acondition C6-1 and a condition C6-1′, the terminal device performstransmission of a measurement report thereof. When satisfying acondition C6-2 and a condition C6-2′, the terminal device stops thetransmission of the measurement report. Note that, the neighbour cell isa cell on the same frequency as that of the secondary cell.

Entering condition C6-1: Mn+Ocn-Hys>Ms+Ocs+Off

Leaving condition C6-2: Mn+Ocn+Hys<Ms+Ocs+Off

Entering condition C6-1′: Mn′+Ocn′-Hys′>Ms′+Ocs′+Off′

Leaving condition C6-2′: Mn′+Ocn′+Hys′<Ms′+Ocs′+Off′

Here, Mn denotes the first measurement result for the neighbour cell (ameasurement offset value specific to the cell is not considered), Mn′denotes the second measurement result for the neighbour cell (ameasurement offset value specific to the cell is not considered), Ocndenotes a cell-specific measurement offset value for the firstmeasurement result with respect to the neighbour cell (0 is set when notconfigured to the neighbour cell), Ocn′ denotes a cell-specificmeasurement offset value for the second measurement result with respectto the neighbour cell (0 is set when not configured to the neighbourcell), Ms denotes the first measurement result for the serving cell (ameasurement offset value specific to the cell is not considered), Ms′denotes the second measurement result for the serving cell (ameasurement offset value specific to the cell is not considered), Ocsdenotes a cell-specific measurement offset value for the firstmeasurement result with respect to the serving cell (0 is set when notconfigured to the serving cell), Ocs′ denotes a cell-specificmeasurement offset value for the second measurement result with respectto the serving cell (0 is set when not configured to the serving cell),Hys denotes a hysteresis parameter for the first measurement result withrespect to the target event, Hys′ denotes a hysteresis parameter for thesecond measurement result with respect to the target event, Off denotesan offset parameter utilized for the first measurement result withrespect to the target event, and Off′ denotes an offset parameterutilized for the second measurement result with respect to the targetevent.

Next, details of a measurement result will be described.

This measurement result is constituted by a measurement identity (measId), a serving cell measurement result (meas Resultserving), and anEUTRA measurement result list (meas Result List EUTRA). The EUTRAmeasurement result list (meas Result List EUTRA) includes a physicalcell identity (physical Cell Identity) and a EUTRA cell measurementresult (meas Result EUTRA). The measurement identity (meas Id) is anidentify utilized for linking the measurement object identity (measObject Id) and the reporting configuration identity (report Config Id)as described above. The physical cell identity (physical Cell Identity)is utilized for identifying a cell. The EUTRA cell measurement result(meas Result EUTRA) is a measurement result for an EUTRA cell. Themeasurement result of a neighbour cell is included only when a relevantevent is generated.

One example of the measurement result will be described.

With the measurement result, both results of the RSRP and the RSRQ forthe target cell are reported. The RSRP and the RSRQ reported at one timeare any one of the first measurement result or the second measurementresult.

As one specific example, the measurement result is reported based on aparameter for determining whether to be the first measurement result orthe second measurement result. A reference for determining whether to bethe first measurement result or the second measurement result is, forexample, a new parameter (report Meas Type). Information indicating toreport the first measurement result or information indicating to reportthe second measurement result is set to the parameter. For example, whenthe information indicating to report the second measurement result isset to the parameter, the terminal device recognizes the parameter,performs the second measurement, transmits the second measurement resulton a measurement report message, and does not transmit the firstmeasurement result.

Note that, the parameter may be used in common with a parameter forspecifying the type of the measurement result utilized for evaluatingthe event triggering criteria (trigger Meas Type). Note that, theparameter may be used in common with a higher-layer parameter forspecifying a measurement method.

Note that, the parameter (report Quantity) may be configured for eachtype of the measurement as a parameter for the RSRP (report QuantityRSRP) and a parameter for the RSRQ (report Quantity RSRQ). For example,when the report Quantity RSRP is configured as the first RSRP and thereport Quantity RSRQ is configured as the second RSRQ, the terminaldevice transmits the first RSRP and the second RSRQ and does nottransmit the second RSRP and the first RSRQ.

As one specific example, when periodic report or event triggeredperiodic report is configured, the first measurement result and thesecond measurement result are periodically and alternatively reported tothe terminal device. For example, the first measurement result isreported in the first report, the second measurement result is reportedin the second report, the first measurement result is reported in thethird report, the second measurement result is reported in the fourthreport, and then, the report is repeatedly and alternately performed.

Note that, the first measurement result and the second measurementresult may not be reported at the same frequency. For example, a cycleat which the first measurement result is reported twice and then thesecond measurement result is reported once may be configured.Specifically, the first measurement result is reported in the firstreport and the second report and the second measurement result isreported in the third report. The number of times of the report isconfigured by a parameter of a higher layer.

As one specific example, the report is performed depending on thecondition for specifying the measurement.

For example, a type of the measurement result to be reported isdetermined depending on the start-up/stop state of a target cell.

For example, the type of the measurement result to be reported isdetermined depending on detection of reference signals. For example,when the CRS is detected and the DRS is not detected, the firstmeasurement result is reported, and when the CRS is not detected and theDRS is detected, the second measurement result is reported. When both ofthe CRS and the DRS are detected, the measurement result having higherreceive power is reported. When neither the CRS nor the DRS is detected,no report is performed or a minimum value is reported.

Note that, a parameter which clearly indicates which type of themeasurement is set may be added to the measurement result so that theterminal device causes the base station device to recognize whether thereported measurement result is the result calculated by the firstmeasurement or the result calculated by the second measurement.

One example of the report of the measurement result will be described.

With the measurement result, results of the first RSRP and the firstRSRQ as well as the second RSRP and the second RSRQ for the target cellare reported.

The terminal device performs the first measurement and the secondmeasurement, and transmits (transfers) the measurement result on ameasurement report message.

When the CRS is not able to be detected, the terminal device performsthe report by setting a minimum value to the first measurement result.When the CRS is not able to be detected, the terminal device does notneed to report the first measurement result.

When the DRS is not able to be detected, the terminal device performsthe report by setting a minimum value to the second measurement result.When the DRS is not able to be detected, the terminal device does notneed to report the second measurement result.

One example of the report of the measurement result will be described.

With the measurement result, results of the RSRP and the RSRQ for thetarget cell and inter-cell interference measurement are reported.Examples of the result of the inter-cell interference measurementinclude receive power, the SINR, and the RSSI measured in aninterference measurement resource.

The terminal device recognizes the parameter, performs the measurementand an inter-cell interference quantity, and transmits the measurementresults on a measurement report message.

Each example of the event, the event triggering criteria, and the reportof the measurement result has been described above. With a combinationthereof, the terminal device reports the first measurement result and/orthe second measurement result to the base station device. In the presentembodiment, though there is no limitation to the combination of theevent, the event triggering criteria, and the report of the measurementresult, one example of a preferable combination will be described below.

One example of the combination of the event, the event triggeringcriteria, and the report of the measurement result will be described.

When the first measurement is performed, a measurement object (measObject) that includes a neighbour cell list or a black list to which aphysical cell identity is configured is configured, a reportconfiguration (report Config) for configuring the event triggered by thefirst measurement and the event triggering criteria is configured, andthey are associated with each other by the ID so that a measurementreport message including the first measurement result (meas Results) istransmitted. Further, when the second measurement is performed, ameasurement object (meas Object) that includes a new neighbour cell listor a new black list to which an extended cell ID is configured isconfigured, a report configuration (report Config) for configuring theevent triggered by the second measurement and the event triggeringcriteria is configured, and they are associated with each other by theID so that a measurement report message including the second measurementresult (meas Results) is transmitted.

That is, the measurement object, the report configuration, and themeasurement result for the first measurement and the measurement object,the report configuration, and the measurement result for the secondmeasurement are configured to the terminal device. That is, the reportconfiguration of the first measurement result and the reportconfiguration of a second measurement result are configuredindividually.

One example of the combination of the event, the event triggeringcriteria, and the report of the measurement result will be described.

When the first measurement is performed, a measurement object (measObject) that includes a neighbour cell list or a black list to which aphysical cell identity is configured is configured, a reportconfiguration (report Config) for configuring the event triggered by thefirst measurement and the event triggering criteria is configured, andthey are associated with each other by the measurement results (measResults) and the ID. Further, when the second measurement is performed,a measurement object (meas Object) that includes a new neighbour celllist or a new black list to which an extended cell ID is configured isconfigured, a report configuration (report Config) for configuring theevent triggered by the second measurement and the event triggeringcriteria is configured, and they are associated with each other by themeasurement results (meas Results) and the ID. When the event triggeredby the first measurement is generated, the first measurement result issubstituted in the measurement result and the transmission by themeasurement report message is performed. When the event triggered by thesecond measurement is generated, the second measurement result issubstituted in the measurement result and the transmission by themeasurement report message is performed.

That is, the measurement object and the report configuration for thefirst measurement and the measurement object and the reportconfiguration for the second measurement are configured, and fields ofthe measurement results are shared between the first measurement and thesecond measurement. The first measurement result or the secondmeasurement result is transmitted by the event.

Thereby, the terminal device is able to report the first measurementresult and the second measurement result to the base station device.

The terminal device of the present embodiment is a terminal devicecommunicating with a base station device, including: a reception unitwhich performs first measurement based on a first RS (CRS) and performssecond measurement based on a second RS (DRS); and a higher layerprocessing unit which reports a result of the first measurement and aresult of the second measurement to the base station device, in whichthe result of the first measurement is reported to the base stationdevice in a first state and the result of the first measurement or theresult of the second measurement is reported to the base station devicein a second state.

As one example, an event by which the first measurement result isreported and an event by which the second measurement result is reportedare configured by the base station device in the second state. Further,as one example, only an event by which the second measurement isreported is configured by the base station device in the second state.Event triggering criteria for reporting the second measurement resultare prescribed by using the result of the second measurement result.

As one example, the first state is a state where configurationinformation on the second RS is not notified and the second state is astate where the configuration information on the second RS is notifiedfrom the base station device. Further, as one example, the first stateis a state where the second measurement information is not configuredand the second state is a state where the second measurement informationis configured from the base station device. In addition, as one example,the second state is a state where the first RS is not transmitted.

Values of transmit power of the PUSCH and PHR (Power Headroom) aredetermined depending on path loss. One example of a method forestimating path loss (channel attenuation value) will be describedbelow.

An estimated value of downlink path loss of a serving cell c iscalculated by the terminal device with use of a formula of PLc=referenceSignal Power−higher layer filtered RSRP. In the formula, the referenceSignal Power is provided by a higher layer. The reference Signal Poweris information based on transmit power of the CRS. In the formula, thehigher layer filtered RSRP is the first RSRP of a reference serving cellfiltered in the higher layer.

When the serving cell c belongs to TAG including a primary cell, withrespect to an uplink primary cell, the primary cell is used forreference serving cells of the reference Signal Power and the higherlayer filtered RSRP. With respect to an uplink secondary cell, a servingcell configured by the pathloss Reference Linking as a higher layerparameter is used for the reference serving cell of the reference SignalPower and the higher layer filtered RSRP. When the serving cell cbelongs to TAG not including a primary cell, the serving cell c is usedfor the reference serving cell of the reference Signal Power and thehigher layer filtered RSRP.

One example of a method for estimating path loss will be described.

An estimated value of downlink path loss of the serving cell c iscalculated by the terminal device with use of a formula of PLc=discoveryReference Signal Power−higher layer filtered RSRP2 in a case of beingconfigured by the higher layer and with use of a formula ofPLc=reference Signal Power−higher layer filtered RSRP in a case of notbeing configured by the higher layer. In the formula, the referenceSignal Power is provided by the higher layer. The reference Signal Poweris information based on transmit power of the CRS. In the formula, thehigher layer filtered RSRP is the first RSRP of a reference serving cellfiltered in the higher layer. In the formula, the discovery ReferenceSignal Power is provided by the higher layer. The discovery ReferenceSignal Power is information based on transmit power of the DRS. In theformula, the higher layer filtered RSRP is the second RSRP of areference serving cell filtered in the higher layer.

The case of being configured by the higher layer is based on, forexample, a configuration of the DRS. The case of being configured by thehigher layer is based on, for example, a configuration of themeasurement. The case of being configured by the higher layer is basedon, for example, a configuration of control of uplink transmit power.

When the serving cell c belongs to TAG including a primary cell, withrespect to an uplink primary cell, the primary cell is used forreference serving cells of the discovery Reference Signal Power and thehigher layer filtered RSRP2. With respect to an uplink secondary cell, aserving cell configured by the pathloss Reference Linking as a higherlayer parameter is used for the reference serving cell of the discoveryReference Signal Power and the higher layer filtered RSRP2. When theserving cell c belongs to TAG not including a primary cell, the servingcell c is used for the reference serving cell of the discovery ReferenceSignal Power and the higher layer filtered RSRP2.

One example of a method for estimating path loss will be described.

An estimated value of downlink path loss of a primary cell is calculatedby the terminal device with use of a formula of PLc=reference SignalPower−higher layer filtered RSRP. The calculation is performed with aformula of PLc=discovery Reference Signal Power−higher layer filteredRSRP2 in a case where the serving cell c is in the stop state and withuse of a formula of PLc=reference Signal Power−higher layer filteredRSRP in a case where the serving cell c is in the start-up state. In theformula, the reference Signal Power is provided by the higher layer. Thereference Signal Power is information based on transmit power of theCRS. In the formula, the higher layer filtered RSRP is the first RSRP ofa reference serving cell filtered in the higher layer. In the formula,the discovery Reference Signal Power is provided by the higher layer.The discovery Reference Signal Power is information based on transmitpower of the DRS. In the formula, the higher layer filtered RSRP2 is thesecond RSRP of a reference serving cell filtered in the higher layer.

The threshold to be compared to the second RSRP is configured by thehigher layer.

When the serving cell c belongs to TAG including a primary cell, withrespect to an uplink primary cell, the primary cell is used forreference serving cells of the reference Signal Power, the discoveryReference Signal Power, the higher layer filtered RSRP, and the higherlayer filtered RSRP2. With respect to an uplink secondary cell, aserving cell configured by the pathloss Reference Linking as a higherlayer parameter is used for the reference serving cell of the referenceSignal Power, the discovery Reference Signal Power, the higher layerfiltered RSRP, and the higher layer filtered RSRP2. When the servingcell c belongs to TAG not including a primary cell, the serving cell cis used for the reference serving cell of the reference Signal Power,the discovery Reference Signal Power, the higher layer filtered RSRP,and the higher layer filtered RSRP2.

One example of a method for estimating path loss will be described.

An estimated value of downlink path loss of a primary cell is calculatedby the terminal device with use of a formula of PLc=reference SignalPower−higher layer filtered RSRP. An estimated value of downlink pathloss of the serving cell c is calculated by the terminal device with aformula of PLc=discovery Reference Signal Power−higher layer filteredRSRP2 in a case where the serving cell c does not belong to TAGincluding a primary cell and the second RSRP is equal to or more thanthe threshold and with use of a formula of PLc=reference SignalPower−higher layer filtered RSRP otherwise. In the formula, thereference Signal Power is provided by the higher layer. The referenceSignal Power is information based on transmit power of the CRS. In theformula, the higher layer filtered RSRP is the first RSRP of a referenceserving cell filtered in the higher layer. In the formula, the discoveryReference Signal Power is provided by the higher layer. The discoveryReference Signal Power is information based on transmit power of theDRS. In the formula, the higher layer filtered RSRP2 is the second RSRPof a reference serving cell filtered in the higher layer.

The threshold to be compared to the second RSRP is configured by thehigher layer.

When the serving cell c belongs to TAG including a primary cell, withrespect to an uplink primary cell, the primary cell is used forreference serving cells of the reference Signal Power and the higherlayer filtered RSRP. With respect to an uplink secondary cell, a servingcell configured by the pathloss Reference Linking as a higher layerparameter is used for the reference serving cell of the reference SignalPower, the discovery Reference Signal Power, the higher layer filteredRSRP, and the higher layer filtered RSRP2. When the serving cell cbelongs to TAG not including a primary cell, the serving cell c is usedfor the reference serving cell of the reference Signal Power, thediscovery Reference Signal Power, the higher layer filtered RSRP, andthe higher layer filtered RSRP2.

Control of downlink power will be described below.

The control of downlink power is determined by EPRE (Energy Per ResourceElement). In this case, the energy per resource element is energy beforeCP (Cyclic Prefix) is inserted. The energy per resource element isaverage energy taking over all constellation points with respect to anapplied modulation method.

The terminal device assumes the EPRE of a downlink cell-specificreference signal, which is fixed over all subframes and is fixed over adownlink system bandwidth until information on reference signal powerspecific to a different cell is received. The EPRE of the downlinkcell-specific reference signal is calculated from downlink referencesignal transmit power provided by a parameter (reference Signal Power)provided by the higher layer. The downlink reference signal transmitpower is defined to be obtained by linearly averaging power of allresource elements carrying the cell-specific reference signal includedin the operating system bandwidth.

The terminal device assumes downlink positioning reference signal EPREwhich is fixed over all OFDM symbols including a positioning referencesignal of a predetermined positioning reference signal being generatedand fixed over the bandwidth of the positioning reference signal.

When the CSI-RS is configured in a serving cell, the terminal deviceassumes the downlink CSI-RS EPRE which is fixed over all subframes withrespect to each CSI-RS resource and fixed over the downlink systembandwidth.

When the DRS is configured in a predetermined cell, the terminal deviceassumes the downlink DRS EPRE which is fixed over all subframes withrespect to each DRS resource and fixed over the downlink systembandwidth.

Details of a method for notifying the terminal device of transmit powerof the PDSCH will be described below. Details of a method for performingnotification based on transmit power of the CRS will be described below.

Ratios of the PDSCH EPRE of the resource element of the PDSCH to eachOFDM symbol to the cell-specific RS EPRE are represented by ρ_(A) andρ_(B). Here, ρ_(A) indicates a ratio of the PDSCH EPRE of the OFDMsymbol not including the CRS to the cell-specific RS EPRE. Here, ρ_(B)indicates a ratio the PDSCH EPRE of the OFDM symbol including the CRS tothe cell-specific RS EPRE. Additionally, ρ_(A) and ρ_(B) are specific toa terminal.

In a terminal device in a transmission mode 8-10 or a terminal device ina transmission mode 1-7 in each of which a terminal-specific RS does notexist in a PRB having the associated PDSCH arranged, the terminal deviceis assumed to have the following ρ_(A) with respect to spatialmultiplexing or PDSCH transmission associated with a multi-user MIMOtransmission method, which is greater than that of the 16QAM, 64QAM, or1 layer. Note that, the similar assumption may be applied also to256QAM.

In a case where the terminal device receives transmission of PDSCH datausing precoding of transmission diversity by four cell-specific antennaports, ρ_(A) is equal to δ_(power-offset)+P_(A)+10 log₁₀(2), and ρ_(A)is equal to δ_(power-offset)+P_(A) in other cases. The δ_(power-offset)is 0 dB in all PDSCH transmission methods other than multi-user MIMO,and P_(A) is a parameter which is provided by the higher layer andspecific to the terminal device.

A cell-specific ratio ρ_(A)/ρ_(B) is determined by P_(B) and the numberof antenna ports of the CRS. Here, P_(B) denotes a cell-specificparameter notified by the higher layer.

Details of a method for notifying the terminal device of transmit powerof the PDSCH will be described below. Details of a method for performingnotification based on transmit power of the DRS will be described below.

Ratios of the PDSCH EPRE of the resource element of the PDSCH to eachOFDM symbol to the DRS EPRE are represented by ρ_(A)′ and ρ_(B)′. Here,ρ_(A)′ indicates a ratio of the PDSCH EPRE of the OFDM symbol notincluding the CRS to the DRS EPRE. Here, ρ_(B)′ indicates a ratio thePDSCH EPRE of the OFDM symbol including the CRS to the DRS EPRE.Additionally, ρ_(A)′ and ρ_(B)′ are specific to a terminal.

In a terminal device in a transmission mode 8-10 or a terminal device ina transmission mode 1-7 in each of which a terminal-specific RS does notexist in a PRB having the associated PDSCH arranged, the terminal deviceis assumed to have the following ρ_(A)′ with respect to spatialmultiplexing or PDSCH transmission associated with a multi-user MIMOtransmission method, which is greater than that of the 16QAM, 64QAM, or1 layer. Note that, the similar assumption may be applied also to256QAM.

In a case where the terminal device receives transmission of PDSCH datausing precoding of transmission diversity by four cell-specific antennaports, ρ_(A)′ is equal to δ_(power-offset)+P_(A)′+10 log₁₀(2), and ρ_(A)is equal to δ_(power-offset)+P_(A)′ in other cases. The δ_(power-offset)is 0 dB in all PDSCH transmission methods other than multi-user MIMO,and P_(A)′ is a parameter which is provided by the higher layer andspecific to the terminal device.

A ratio ρ_(A)′/ρ_(B)′ is determined based on P_(B)′. Here, P_(B)′denotes a parameter notified by the higher layer.

With the details of the aforementioned embodiments, it is possible toimprove transmission efficiency in a radio communication system in whicha base station device communicates with a terminal device.

A program which runs in the base station device 3 and the terminaldevice 1 concerning the invention may be a program that controls a CPU(Central Processing Unit) and the like (program that causes a computerto function) such that the functions in the aforementioned embodimentsconcerning the invention are realized. The pieces of information handledby the devices are temporarily accumulated in a RAM (Random AccessMemory) during the processing thereof, and then stored in various ROMssuch as a flash ROM and HDDs (Hard Disk Drives) and read, corrected, andwritten by the CPU when necessary.

A part of the terminal device 1 and the base station device 3 in theaforementioned embodiments may be realized by a computer. In such acase, a program to realize this control function may be recorded in acomputer-readable recording medium, and a computer system may be causedto read and execute the program recorded in the recording medium and,thereby, the control function may be realized.

Note that, the “computer system” used herein refers to a computer systemthat is incorporated in the terminal device 1 or the base station device3 and that includes an OS and hardware such as a peripheral device. The“computer-readable recording medium” refers to a portable medium such asa flexible disk, a magneto-optical disk, a ROM, or a CD-ROM, or astorage device such as a hard disk incorporated in the computer system.

Further, the “computer-readable recording medium” may include one thatdynamically retains the program for a short time period such as acommunication cable used when the program is transmitted through anetwork such as the Internet or a communication line such as a telephoneline and, in such a case, one that retains the program for a fixed timeperiod such as a volatile memory in a computer system used as a serveror a client. The “program” may be one to realize a part of the functionsdescribed above, or may also be one that is able to realize the part incombination with the program already recorded in the computer system.

Furthermore, the base station device 3 according to the aforementionedembodiments can be realized as an aggregation (a device group) that isconfigured from multiple devices. Each device that constitutes thedevice group may be provided with a part or all of each function or eachfunctional block of the base station device 3 according to theaforementioned embodiments. The device group may have each generalfunction or each general functional block of the base station device 3.Furthermore, the terminal device 1 according to the embodiment describedabove can also communicate with the base station device as theaggregation.

The base station device 3 in the aforementioned embodiment may be EUTRAN(Evolved Universal Terrestrial Radio Access Network). The base stationdevice 3 in the aforementioned embodiments may have a part or all offunctions of a higher node to eNodeB.

A part or all of the terminal device 1 and the base station device 3 inthe aforementioned embodiments may be realized as an LSI which is atypical integrated circuit. Each functional block of the terminal device1 and the base station device 3 may be individually formed into a chip,or a part or all thereof may be integrated and formed into a chip.Further, a method for making into an integrated circuit is not limitedto the LSI and a dedicated circuit or a versatile processor may be usedfor realization. Further, in a case where a technique for making into anintegrated circuit in place of the LSI appears with advance of asemiconductor technique, an integrated circuit by the technique is alsoable to be used.

Note that, though a terminal device has been described as one example ofa terminal device or a communication device in the aforementionedembodiments, the invention of the present application is not limitedthereto and is applicable to stationary or unmovable electronicequipment which is installed indoors or outdoors such as, for example, aterminal device or a communication device including AV equipment,kitchen equipment, cleaning/washing machine, air conditioning equipment,office equipment, automatic vending machine, other domestic equipment,and the like.

As above, the embodiments of the invention have been described in detailwith reference to drawings, but specific configurations are not limitedto the embodiments, and a design and the like which are not departedfrom the main subject of the invention are also included. The inventionmay be modified in various manners within the scope of the claims and anembodiment achieved by appropriately combining technical means disclosedin each of different embodiments is also encompassed in the technicalscope of the invention. In addition, configurations obtained byreplacing elements that have been described in the embodiments describedabove and that exert similar effects are also included.

INDUSTRIAL APPLICABILITY

The invention is able to be applied to a communication device, anelectronic device, domestic electric appliance, other devices, and thelike.

REFERENCE SIGNS LIST

-   -   1 (1A, 1B, 1C) terminal device    -   3 base station device    -   101 higher layer processing unit    -   103 control unit    -   105 reception unit    -   107 transmission unit    -   301 higher layer processing unit    -   303 control unit    -   305 reception unit    -   307 transmission unit    -   1011 radio resource control unit    -   1013 subframe configuration unit    -   1015 scheduling information interpretation unit    -   1017 CSI report control unit    -   3011 radio resource control unit    -   3013 subframe configuration unit    -   3015 scheduling unit    -   3017 CSI report control unit    -   1301 measurement unit    -   13011 layer 1 filtering unit    -   13012 layer 3 filtering unit    -   13013 report reference evaluation unit

1-18. (canceled)
 19. A terminal device, comprising: a measurement unit which performs first measurement for performing measurement by using a first reference signal and second measurement for performing measurement by using a second reference signal; a reception unit which receives information on criteria for triggering of a measurement reporting event; and a transmission unit which transfers a measurement report message including a measurement result, wherein the information on criteria for triggering of the measurement reporting event includes information on triggering criteria of an event of a first measurement reporting and information on triggering criteria of an event of a second measurement reporting, and the measurement report message includes a result of the first measurement in a case where the first measurement reporting is triggered, and the measurement report message includes a result of the second measurement in a case where the second measurement reporting is triggered.
 20. The terminal device according to claim 19, wherein the information on triggering criteria of the event of the first measurement reporting includes first information for specifying a triggering quantity used for evaluating criteria for triggering of an event of a measurement reporting related to the first reference signal.
 21. The terminal device according to claim 20, wherein the first information is information indicating RSRP (Reference Signal Received Power) or RSRQ (Reference Signal Received Quality).
 22. The terminal device according to claim 20, wherein the first reference signal is a CRS (Cell-specific Reference Signal).
 23. The terminal device according to claim 19, wherein the information on triggering criteria of the event of the second measurement reporting includes second information for specifying a triggering quantity used for evaluating criteria for triggering of an event of a measurement reporting related to the second reference signal.
 24. The terminal device according to claim 23, wherein the second information is information indicating RSRP (Reference Signal Received Power).
 25. The terminal device according to claim 23, wherein the second reference signal is a CSI-RS (Channel State Information Reference Signal).
 26. A base station device, comprising: a transmission unit which transmits information on criteria for triggering of a measurement reporting event; and a reception unit which receives a measurement report message including a measurement result, wherein the information on criteria for triggering of the measurement reporting event includes information on triggering criteria of an event of a first measurement reporting and information on triggering criteria of an event of a second measurement reporting, and the measurement report message includes a result of first measurement for performing measurement by using a first reference signal in a case where the first measurement reporting is triggered, and the measurement report message includes a result of second measurement for performing measurement by using a second reference signal in a case where the second measurement reporting is triggered.
 27. The base station device according to claim 26, wherein the information on triggering criteria of the event of the first measurement reporting includes first information for specifying a triggering quantity used for evaluating criteria for triggering of an event of a measurement reporting related to the first reference signal.
 28. The base station device according to claim 27, wherein the first information is information indicating RSRP or RSRQ.
 29. The base station device according to claim 27, wherein the first reference signal is a CRS (Cell-specific Reference Signal).
 30. The base station device according to claim 26, wherein the information on triggering criteria of the event of the second measurement reporting includes second information for specifying a triggering quantity used for evaluating criteria for triggering of an event of a measurement reporting related to the second reference signal.
 31. The base station device according to claim 30, wherein the second information is information indicating RSRP (Reference Signal Received Power).
 32. The base station device according to claim 30, wherein the second reference signal is a CSI-RS (Channel State Information Reference Signal).
 33. A communication method performed by a terminal device, the communication method comprising: a step of performing first measurement for performing measurement by using a first reference signal and second measurement for performing measurement by using a second reference signal; a step of receiving information on criteria for triggering of a measurement reporting event; and a step of transferring a measurement report message including a measurement result, wherein the information on criteria for triggering of the measurement reporting event includes information on triggering criteria of an event of a first measurement reporting and information on triggering criteria of an event of a second measurement reporting, and the measurement report message includes a result of the first measurement in a case where the first measurement reporting is triggered, and the measurement report message includes a result of the second measurement in a case where the second measurement reporting is triggered. 